Acessibilidade / Reportar erro

The effectiveness of Kangaroo Mother Care in hospitalization period of preterm and low birth weight infants: systematic review and meta-analysis

Abstract

Objective:

To evaluate the effectiveness of kangaroo mother care (KMC) in reducing the length of hospital stay of preterm and/or low birth weight infants.

Source:

Cochrane Library, Pubmed, Embase, LILACS, and Scielo. Randomized clinical trials without time or language limit were included. The intervention was the KMC in preterm and/or low birth weight infants born in health facilities compared to conventional care. The article selection was performed by a pair of reviewers independently. The methodological quality assessment was performed using the tool Risk of Bias 2.

Summary of the findings:

Eight hundred and sixty-four citations were identified and 12 were selected for data extraction. There was a reduction in the length of hospital stay in days in the KMC group compared to the conventional care group, with a statistically significant difference (MD -1.75, 95% CI -3.22 to -0.28). The subgroup that underwent the intervention for more than six hours daily did not show a statistical difference for the length of hospital stay outcome (MD -0.79, 95% CI -2.52 to 0.90), while the subgroup that underwent the intervention for less than six hours daily showed a reduction in this outcome with a statistically significant difference (MD -4.66, 95% CI -7.15 to -2.17).

Conclusions:

KMC is a safe and low-cost intervention that has been shown to be effective in reducing the length of hospital stay of preterm and/or low birth weight infants.

KEYWORDS
Infant; Premature; Infant; low birth weight; Kangaroo-Mother Care Method

Introduction

Every year, 30 million infants are born in risk conditions worldwide. According to the World Health Organization, these conditions include preterm births, infants small for the gestational age (SGA) or at risk of becoming ill, risk of death, and disabilities.11. World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/.
http://www.who.int/maternal_child_adoles...

Prematurity is a birth that occurs before 37 weeks of gestation and is considered low birth weight (LBW) infants when born with less than 2500 g.11. World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/.
http://www.who.int/maternal_child_adoles...

Most infant deaths still occur in the neonatal period. In 2017, 2.5 million deaths were estimated to have occurred in the first 28 days of life. Approximately 80% of these were LBW infants, while two-thirds of them were preterm infants.11. World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/.
http://www.who.int/maternal_child_adoles...

Reducing neonatal mortality to 12 or less per 1,000 live births and providing the kangaroo mother care (KMC) or other humanized care method to at least 75% of eligible infants are among the objectives of the Every Newborn Action Plan launched by the United Nations International Children’s Emergency Fund (UNICEF).11. World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/.
http://www.who.int/maternal_child_adoles...

Since existing methods to prevent infant deaths in the conventional neonatal care involve a high cost and require qualified human resources and permanent logistical support, the KMC is an effective and safe alternative for infants clinically stable,22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. especially in developing countries where 12% are preterm infants and 60%, occur in Africa and South Asian countries.11. World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/.
http://www.who.int/maternal_child_adoles...

The KMC was developed by Rey and Martinez in Bogotá, Colombia, in 1978; its aim was to promote the early discharge of LBW, preterm, or SGA infants. It was conceived as a proposal to solve overcrowding, shortage of equipment, absence or unpreparedness of professionals, and high cross-infection rates.22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8.

KMC is a standardized and protocolized care system for LBW and/or preterm infants at birth, based on skin-to-skin contact between the infant and the mother. It seeks to empower the mother and family, gradually transferring the ability and responsibility of being the primary caregivers of their infant, meeting their physical and emotional needs.33. Fundación Canguro y Departamento de Epidemiología Clínica y Bioestadística Facultad de Medicina – Pontificia Universidade Javeriana. Guías de práctica basadas en evidencia para la óptima utilización del Método Madre Canguro em el recién nacido pretérmino y/o de bajo peso al nacer. 2007 [cited 2019 Mar 19]. Available from: http://www.quenoosseparen.info/documen-tos/guias_evidencia.pdf
http://www.quenoosseparen.info/documen-t...
Besides skin-to-skin contact, its other components are exclusive breastfeeding (ideally), starting in the hospital and continuing at home, early discharge, building social support, and follow-up.44. Nyqvist KH, Expert Group of the International Network on Kangaroo Mother CareAnderson GC, Bergman N, Cattaneo A, Charpak N, et al. State of the art and recommendations. Kangaroo mother care: application in a high-tech environment. Acta Paediatr. 2010;99:812–9.

Although the effectiveness of KMC is evidenced in systematic reviews, these are focused on analyzing the reduction in morbidity and mortality,55. Conde-Agudelo A, Belizán JM, Diaz-Rossello J. Kangaroo mother care to reduce morbidity and mortality in low birthweight infants. Cochrane Database Syst Rev. 2011(3):CD002771. the neonatal pain,66. Johnston C, Campbell-Yeo M, Disher T, Benoit B, Fernandes A, Streiner D, et al. Skin-to-skin care for procedural pain in neonates. Cochrane Database Syst Rev. 2017;2:CD008435.,77. Pillai Riddell RR, Racine NM, Gennis HG, Turcotte K, Uman LS, Horton RE, et al. Non-pharmacological management of infant and young child procedural pain. Cochrane Database Syst Rev. 2015;2015:CD006275.,88. Disher T, Benoit B, Johnston C, Campbell-Yeo M. Skin-to-skin contact for procedural pain in neonates: acceptability of novel systematic review synthesis methods and GRADEing of the evidence. J Adv Nurs. 2017;73:504–19. and its association with breastfeeding.99. Karimi FZ, Sadeghi R, Maleki-Saghooni N, Khadivzadeh T. The effect of mother-infant skin to skin contact on success and duration of first breastfeeding: a systematic review and metaanalysis. Taiwan J Obstet Gynecol. 2019;58:1–9.,1010. Ghojazadeh M, Hajebrahimi S, Pournaghi-Azar F, Mohseni M, Derakhshani N, Azami-Aghdash S. Effect of kangaroo mother care on successful breastfeeding: a systematic review and meta-analysis of randomised controlled trials. Rev Recent Clin Trials. 2019;14:31–40.,1111. Vaivada T, Gaffey MF, Bhutta ZA. Promoting early child development with interventions in health and nutrition: a systematic review. Pediatrics. 2017;140:e20164308.,1212. Sharma D, Farahbakhsh N, Sharma S, Sharma P, Sharma A. Role of kangaroo mother care in growth and breast feeding rates in very low birth weight (VLBW) neonates: a systematic review. J Matern Fetal Neonatal Med. 2019;32:129–42.,1313. Parker LA, Sullivan S, KruegerC, KelechiT, Mueller M. Strategies to increase milk volume in mothers of VLBW infants. MCN Am J Matern Child Nurs. 2013;38:385–90.,1414. Renfrew MJ, Dyson L, McCormick F, Misso K, Stenhouse E, King SE, et al. Breastfeeding promotion for infants in neonatal units: a systematic review. Child Care Health Dev. 2010;36:165–78. Therefore, a synthesis of evidence to assess whether the KMC effectively reduces the length of LBW and/or preterm infants’ hospital stay is still needed.

Having a shorter hospital stay provides families with anticipation of returning home and living with their social support. In addition, optimizing hospital beds and some studies reduce the costs in groups that used the KMC method as intervention.1515. Sharma D, Murki S, Oleti TP. Study comparing. Kangaroo Ward Care" with "Intermediate Intensive Care" for improving the growth outcome and cost effectiveness: randomized control trial. J Matern Fetal Neonatal Med. 2018;31:2986–93.,1616. Charpak N, Ruiz-Peláez JG, Figueroa CZ, Charpak Y. Kangaroo mother versus traditional care for newborn infants </=2000 Grams: a randomized, controlled trial. Pediatrics. 1997;100:682–8.,1717. Sloan NL, Camacho LW, Rojas EP, Stern C. Kangaroo mother method: randomised controlled trial of an alternative method of care for stabilised low-birthweight infants. Maternidad Isidro Ayora Study Team. Lancet. 1994;344:782–5.,1818. Cattaneo A, Davanzo R, Worku B, SurjonoA, Echeverria M, Bedri A, et al. Kangaroo mother care for low birthweight infants: a randomized controlled trial in different settings. Acta Paediatr. 1998;87:976–85.

Thus, the objective of this systematic review and meta-analysis was to evaluate the effectiveness of KMC in reducing the length of hospital stay of preterm and/or LBW infants.

Methods

This is a systematic review and meta-analysis registered on the International Prospective Register of Systematic Reviews (PROSPERO) platform (https://www.crd.york.ac.uk/prospero) on April 28, 2020, under code CRD42020171496.

Using the PICOS criteria, the following question was used to guide the study: What is the effectiveness of the kangaroo mother care in reducing the length of hospital stay of preterm and/or LBW infants?

P (population): preterm infants (gestational age of less than 37 weeks) and/or infants weighing less than 2500 g at birth;

I (intervention): kangaroo mother care (also known as kangaroo position or skin-to-skin contact);

C (comparison): conventional neonatal care;

O (outcome): length of hospital stay; and

S (study design): randomized clinical trial (RCT).

Inclusion criteria

Population of interest

Infants with a gestational age of less than 37 weeks and/or weighing less than 2500 g at birth born in health facilities.

Type of intervention

Intervention with kangaroo mother care, also known as kangaroo position or skin-to-skin contact.

Control group

Studies with a control group in which infants were submitted to conventional neonatal care were included.

Conventional neonatal care refers to care where the infant is kept in an incubator and/or heated crib. The mother is allowed to visit, touch, and breastfeed. The baby is not placed in the kangaroo position (skin-to-skin contact).

Evaluated outcome

Length of hospital stay.

Type of study included

Studies included were RCTs.

Exclusion criteria

Studies with combined interventions, such as massage, other modalities of kangaroo mother care, plastic bags for heating infants, kangaroo mother care beginning in the delivery room, and kangaroo mother care at home, were excluded. There were no restrictions regarding the date and language of publication.

Methods for study identification

Bibliographic databases

The following databases were searched on March 13, 2020: Cochrane Library, Pubmed, Embase, Scielo, and LILACS. The search was updated in the same databases on March 19, 2021.

Search strategy

Keywords were defined using DECs (Descriptors in Health Sciences), MeSH (Medical Subject Headings), and Emtree. The terms were combined using the Boolean operators OR and AND. The databases search strategy can be found in the Supplementary Material 1.

Data selection and analysis

Study selection and methodological quality assessment

After obtaining the search strategy results, accountability and duplicate exclusion were performed using the platform Covidence (https://www.covidence.org).1919. Covidence Systematic Review Software, Veritas Health Innovation, Melbourne, Australia. [Cited 2021 Mar 20]. Available from: http://www.covidence.org.
http://www.covidence.org...
Then, titles and abstracts were read for study eligibility evaluation, which was performed by a pair of reviewers independently, with conflicts being resolved by consensus. After reading the abstracts, the selected articles were read in full. When considered eligible, they were included in the methodological quality assessment stage using the Cochrane Collaboration tool Risk of Bias 22020. Higgins JP, Sterne JA, Savović J, Page MJ, Hróbjartsson A, Boutron I, et al. A revised tool for assessing risk of bias in randomized trials. In: Chandler J, McKenzie J, Boutron I, Welch V (editors). Cochrane methods. Cochrane Database Syst Rev; 2016;10:CD201601. for assessing the risk of bias in the RCTs.

The process of describing the study selection was conducted based on the PRISMA Flow Diagram (http://www.equator-network.org/reporting-guidelines/prism/).2121. Moher D, Liberati A, Tetzlaff J, Altman DG, Group PRISMA. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoSMed. 2009;6:e1000097.

Extraction and statistical analysis of data from included studies

The data were extracted according to pre-specified criteria, including information about the study (number of participants, gestational age at birth, birth weight, and assistance types used), intervention characteristics (place, time, type, and frequency), and length of hospital stay in days. The assistance types refer to the description of the intervention used in the KMC group.

The outcome value was obtained at hospital discharge in both groups, being collected using continuous data (mean and standard deviation) and the total number of participants.

The software Review Manager (version 5.3)2222. The Nordic Cochrane Centre, The Cochrane Collaboration. Review Manager (RevMan). Version 5.3. Conpenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration; 2014. was used to calculate the effect sizes as mean differences (MDs), adopting a 95% confidence interval (CI). A random-effects model was used for meta-analysis.

The statistical heterogeneity between studies was assessed using the I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. statistic. The following classification was applied to heterogeneity indicators: unimportant, between 0% and 40%; moderate, between 30% and 60%; substantial, between 50% and 90%; and considerable, between 75% and 100%.2323. Higgins JP, Tomas J. Cochrane handbook for systematic reviews of interventions. 2nd ed. Oxford: Wiley Blackwell; 2019.

Results

The search in the abovementioned databases identified 1636 citations. Of these, 292 were duplicate studies. Based on the titles and abstracts, 572 studies were analyzed and 398 studies were excluded. Thus, 174 studies were read in full. After such full-text reading, 162 studies were excluded for the following reasons: a) they were study protocols (55 studies); b) study outcomes were not of interest to the research (43 studies); c) the study design was not RCT (30 studies); d) comparisons were not of interest to the research (11 studies); e) for duplicity (8 studies); f) interventions were not of interest to the research (7 studies); g) they were just congress abstracts or letters to the editor (7 studies); and h) the population studied was not of interest to the research (1 study). Twelve studies were selected for data extraction, as shown in Fig. 1. The study by Tessier et al.2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17. was subdivided into three according to the birth weight of participants because there was no result of the three subgroups sum in the full text of the article. Therefore, 14 studies were considered in the analysis, not 12.

Figure 1
Flow diagram of literature search and included articles.

Characteristics of the studies

Twelve studies, including 816 infants, met the inclusion criteria. All studies were performed in developing countries: Nepal,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23. India,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9. Malaysia,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. Taiwan,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. Indonesia,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. Kenya,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. and Colombia.2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17. Samples ranged from 28[29] to 488 [24] infants. The characteristics of the studies are shown in the Supplementary Material 2.

Six studies included LBW infants weighing less than 2500 g,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7. five studies included LBW infants weighing less than 1500 g,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. and one study classified infants according to their gestational age between 34 and 36 weeks.3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.

In most studies, congenital malformations, perinatal complications, critically ill mothers, or mothers refusing to take part in the research were exclusion criteria. One study used severe perinatal asphyxia as an exclusion criterion.3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.

Four studies did not report the discharge criteria from where they were conducted.2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. Five studies described the minimum weight as a discharge criterion: 1300 g,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9. 1400 g,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23. 1700 g,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17. 1750 g,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. and 1800 g.3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. Five studies used weight gain for three consecutive days as a discharge criterion.2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. Other discharge criteria used included: absence of diseases and of use of intravenous medications,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23. infants essentially in breastfeeding,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23. body temperature maintenance without assistance,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23. mother confidence in baby care at home,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23. and specific hospital criteria.2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.

In eight studies, the KMC duration was longer than six hours daily,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. while in four studies its duration was shorter than six hours daily.2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.

KMC effect on the length of hospital stay

Twelve studies reported the length of hospital stay,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. totaling 1,636 infants. The data combination showed that KMC had the effect of reducing the hospital stay duration in the group submitted to this intervention compared to the group submitted to conventional care, with a statistically significant difference (MD -1.75, 95% CI -3.22 to -0.28). The heterogeneity was considerable (I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 85%). Clinically, the length of hospital stay varies from 3 days, 5 hours, and 16 minutes to 6 hours and 43 minutes, with a mean hospital stay 1 day and 18 hours shorter in the intervention group when compared to the control group (Fig. 2).

Figure 2
Comparison between Kangaroo mother care vs. conventional care regarding the length of hospital stay outcome. CI, confidence interval; SD, standard deviation; IV, inverse variance.

Subgroup analysis

KMC effect on the length of hospital stay when its duration was longer than six hours daily

Eight studies reported the intervention use for more than six hours daily,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. totaling 1,336 infants. The analysis of this subgroup showed no statistical difference for the length of hospital stay outcome in the group submitted to the KMC compared to the group submitted to conventional care (MD -0.81, 95% CI -2.52 to 0.90). The heterogeneity was considerable (I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 89%). Clinically, the length of hospital stay varies from 2 days, 13 hours, and 26 minutes less to 23 hours and 16 minutes more, with a mean hospital stay duration 18 hours and 57 minutes shorter in the intervention group compared to the control group (Fig. 3).

Figure 3
Comparison between Kangaroo mother care with duration longer than six hours daily vs. conventional care regarding the length of hospital stay outcome. CI, confidence interval; SD, standard deviation; IV, inverse variance.

KMC effect on the length of hospital stay when its duration was shorter than six hours daily

Four studies reported the intervention use for less than six hours daily,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. totaling 300 infants. The data combination showed that KMC had the effect of reducing the hospital stay duration in the group submitted to this intervention compared to the group submitted to conventional care, with a statistically significant difference (MD -4.66, 95% IC -7.15 to -2.17). The heterogeneity was unimportant/moderate (I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 38%). Clinically, the length of hospital stay varies from 7 days and 3 hours to 2 days and 4 hours, with a mean hospital stay duration 4 days, 15 hours, and 50 minutes shorter in the intervention group when compared to the control group (Fig. 4).

Figure 4
Comparison between Kangaroo mother care with duration shorter than six hours daily vs. conventional care regarding the length of hospital stay outcome. CI, confidence interval; SD, standard deviation; IV, inverse variance.

Risk of bias assessment

The risk of bias assessment is shown in Fig. 5.

Figure 5
The risk of bias assessment.

Risk of bias arising from the randomization process

Eight studies2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. presented the result "Some concern" for bias in the randomization process, while four studies2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. presented “Low risk” result.

Regarding the allocation sequence, the process implemented in seven studies2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. was appropriate: table of random numbers,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7. randomized blocks randomly mixed before being sealed,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23. computerized minimization,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. and computerized generation of random numbers.3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. Five studies2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. did not report how the allocation sequence process was performed.

Regarding the allocation concealment, four studies2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. used sealed envelopes. Eight studies2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23., 3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. did not provide information on the allocation concealment.

None of the studies showed problems of imbalance between the intervention and control groups.

Risk of bias arising from deviations from the intended intervention

Six studies were classified as “Low risk”2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. and six studies were classified as “Some concern”2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. for bias arising from deviations from the intended intervention.

Due to the intervention nature, none of the studies blinded the participants or the health care team. The seven studies classified as “Some concern” did not inform whether there was a deviation from the intended intervention because of the study context. In the other five studies, classified as “Low risk”, changes were consistent with what would occur outside the trial context.

In all studies, a proper analysis was performed to estimate the effect of the assigned intervention.

Risk of bias arising from missing data on the assessed outcome

All studies,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. except one,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23. were classified as “Low risk of bias” for the length of hospital stay outcome. Data on this outcome were available to all or almost all participants in the studies firstly mentioned above.

The study by Acharya et al.1919. Covidence Systematic Review Software, Veritas Health Innovation, Melbourne, Australia. [Cited 2021 Mar 20]. Available from: http://www.covidence.org.
http://www.covidence.org...
was classified as “High risk” for the length of hospital stay outcome because there was no information on whether the data were available to all participants. In addition, there was no evidence of absence of bias in the results.

Risk of bias arising from the outcome assessment

All studies2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. were classified as "Low risk" for the length of hospital stay outcome. Although most studies did not report whether the outcome evaluators were blinded, there was no evidence that the measuring method of this outcome was inadequate, that there was a difference in the outcome assessment between groups, or that the outcome assessment was influenced by knowledge of the intervention received.

Risk of bias arising from the reported result selection

Six studies2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. were classified as “Some concern” for the length of hospital stay outcome considering the risk of bias arising from the reported result selection because they did not inform whether the data that produced such result was analyzed according to a pre-established analysis plan. The other six studies2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. were classified as “Low risk” for the outcome studied in this criterion.

Discussion

Through the systematic review detailed above, evidence was found that KMC is associated with a reduction in the length of hospital stay of preterm and/or LBW infants.

This result meets one of the purposes intended when the KMC was created, which include the following components: 1) the kangaroo position, 2) the kangaroo feeding policy, and 3) the kangaroo discharge policy (early discharge in kangaroo position).1616. Charpak N, Ruiz-Peláez JG, Figueroa CZ, Charpak Y. Kangaroo mother versus traditional care for newborn infants </=2000 Grams: a randomized, controlled trial. Pediatrics. 1997;100:682–8.

Early (timely) hospital discharge reduces overcrowding in neonatal units, thus reducing the chances of infants contracting hospital infections and the economic impact of hospital stay imposed on families of infants. Additionally, it could also reduce the overall cost of health services.1717. Sloan NL, Camacho LW, Rojas EP, Stern C. Kangaroo mother method: randomised controlled trial of an alternative method of care for stabilised low-birthweight infants. Maternidad Isidro Ayora Study Team. Lancet. 1994;344:782–5.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.

Considering the parameters for heterogeneity described in the Cochrane Handbook for Systematic Reviews of Interventions,2323. Higgins JP, Tomas J. Cochrane handbook for systematic reviews of interventions. 2nd ed. Oxford: Wiley Blackwell; 2019. the meta-analysis of the 12 studies showed an I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 85% (considerable), which represents a high degree of heterogeneity. Thus, a subgroup analysis was performed, where one subgroup was submitted to the intervention for more than six hours daily and the other, for less than six hours daily.

The subgroup that underwent KMC for more than six hours a day presented an I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 89% (considerable), while the subgroup that underwent this intervention for less than six hours a day presented an I22. Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8. = 38% (unimportant/ moderate).

When analyzing the heterogeneity of the full chart of studies and of the chart of the group that performed the intervention for more than six hours daily, clinical heterogeneity was found, which consists of the difference between the characteristics of the studies.3636. Santos EJ, Cunha M. Critical interpretation of statistical results of a meta-analysis: methodological strategies. Millenium. 2013;44:85–98. This difference between study characteristics is believed to be due to the discharge criteria used —some studies used satisfactory weight gain as a criterion, while others used different criteria, such as the type of delivery. Some infant characteristics also appeared to affect the heterogeneity, since most studies used the birth weight as an inclusion criterion. One study3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. used the gestational age as an inclusion criterion.

Eight studies were analyzed in relation to the reported intervention performance for more than six hours daily,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.,3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. totaling 1,336 infants. This analysis showed no statistical difference for the length of hospital stay outcome in the group that performed KMC when compared to the group that underwent conventional care. The clinical difference was a length of hospital stay 18 hours and 57 minutes (-0.81 days) shorter than that of the control group, ranging between 2 days, 13 hours, and 26 minutes less to 23 hours and 16 minutes more. When the length of hospital stay is reduced, there is also a reduction in the costs imposed on the infant family2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,3737. Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42. and on the health system,1717. Sloan NL, Camacho LW, Rojas EP, Stern C. Kangaroo mother method: randomised controlled trial of an alternative method of care for stabilised low-birthweight infants. Maternidad Isidro Ayora Study Team. Lancet. 1994;344:782–5.,3737. Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42.,3838. Rojas MA, Kaplan M, Quevedo M, Sherwonit E, Foster L, Ehrenkranz RA, et al. Somatic growth of preterm infants during skin-to-skin care versus traditional holding: a randomized, controlled trial. J Dev Behav Pediatr. 2003;24:163–8. in addition to the bed turnover promotion in neonatology units.

The study by Acharya et al.2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23. demonstrated a longer hospital stay in the group that received the KMC. The authors state that this outcome is probably related to the discharge criterion (weight greater than 1600 g) and to the fact that the infants in the control group started the study with a weight greater than that of the intervention group infants (1415 g +/- 174.91 g x 1362.3 g +/- 240.14 g). Multivariate analysis was performed to eliminate possible final result confounders for this difference.

Chwo et al.3333. ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42. also demonstrated a longer hospital stay in the intervention group than in the control group (conventional care). The authors attribute this result to the infant characteristics and to the hospital discharge criterion. Subjects in this study were classified as late preterm infants (34 to 36 weeks) weighing more than 2000 g, which differs from other studies, whose subjects weighed less than 2000 g.2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7. The discharge criterion used was maternal discharge according to the postpartum time, being three days for vaginal delivery and five days for cesarean delivery. Additionally, the intervention group had two outliers, although the analysis showed their inclusion did not interfere with the outcome.

The study by Gathwala et al.3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7. showed that the group submitted to the KMC had a hospital stay significantly shorter than that of the control group. This result is in line with other studies that show similar results.1616. Charpak N, Ruiz-Peláez JG, Figueroa CZ, Charpak Y. Kangaroo mother versus traditional care for newborn infants </=2000 Grams: a randomized, controlled trial. Pediatrics. 1997;100:682–8.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3939. Bier JA, Ferguson AE, Morales Y, Liebling JA, Archer D, Oh W, et al. Comparison of skin-to-skin contact with standard contact in low-birth-weight infants who are breast-fed. Arch Pediatr AdolescMed. 1996;150:1265–9.,4040. Roberts KL, Paynter C, McEwan B. A comparison of kangaroo mother care and conventional cuddling care. Neonatal Netw. 2000;19:31–5. The infants studied had birth weights below 1800 g and were followed up until reaching three months of age. They continued receiving the intervention even after hospital discharge.

The studies by Kadam et al.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8. Suman et al.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23. Ghavane et al.,3131. Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9. and Mwendwa et al.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. did not show a statistically significant difference, but demonstrated a reduction in hospital stay varying from 1 hour and 55 minutes (-0.08 days) [29] to 1 day and 19 hours (-1.80 days)[35] in favor of the intervention group. In the study by Mwendwa et al.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8. infants were divided by weight, and the group with the highest weight (1500 to 1750 g) had a significantly shorter hospital stay in the intervention group when compared to the control group. All four studies used satisfactory weight gain as a hospital discharge criterion.

In the study by Tessier et al.,2424. Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17. the infants were subdivided according to their birth weight. Infants weighing between 1201 g and 1500 g receiving KMC had a shorter hospital stay than infants who received conventional care. There was no statistically significant difference between infants weighing less than 1201 g and more than 1500 g.

Four studies reported the intervention for less than six hours daily,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. totaling 300 infants. The data combination analysis of this subgroup showed that KMC had the effect of reducing the length of hospital stay in the group submitted to this intervention compared to the group submitted to conventional care, with a statistically significant difference and low heterogeneity between them.

The studies by Ramanathan et al.2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23. and Lumbanraja et al.3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92. demonstrated a statistically significant reduction in the length of hospital stay of infants submitted to the KMC compared to the group that received conventional care. This result confirms the results of other studies.1616. Charpak N, Ruiz-Peláez JG, Figueroa CZ, Charpak Y. Kangaroo mother versus traditional care for newborn infants </=2000 Grams: a randomized, controlled trial. Pediatrics. 1997;100:682–8.,3030. Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.

The study by Ali et al.2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60. has shown that infants who received conventional care remained hospitalized for longer periods compared to the infants who received the intervention. Although a statistically significant difference has not been demonstrated, the reduction in the hospitalization duration in more than one day in the intervention group contributes to reducing overcrowding in neonatal units.2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.

The study by Boo and Jamli3232. Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6. demonstrated a statistically significant difference, despite its short intervention time (one hour daily). This result is consistent with that of other studies using short-duration KMC.2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.

Studies show that even when performed for short periods, the KMC is associated with a high breastfeeding rate, which facilitates an early discharge.33. Fundación Canguro y Departamento de Epidemiología Clínica y Bioestadística Facultad de Medicina – Pontificia Universidade Javeriana. Guías de práctica basadas en evidencia para la óptima utilización del Método Madre Canguro em el recién nacido pretérmino y/o de bajo peso al nacer. 2007 [cited 2019 Mar 19]. Available from: http://www.quenoosseparen.info/documen-tos/guias_evidencia.pdf
http://www.quenoosseparen.info/documen-t...

In the systematic review conducted by Conde-Agudelo et al.55. Conde-Agudelo A, Belizán JM, Diaz-Rossello J. Kangaroo mother care to reduce morbidity and mortality in low birthweight infants. Cochrane Database Syst Rev. 2011(3):CD002771. for the length of hospital stay outcome, statistical differences were not found between groups. Three studies included for this outcome compared the infants receiving KMC with the conventional cuddling care.3838. Rojas MA, Kaplan M, Quevedo M, Sherwonit E, Foster L, Ehrenkranz RA, et al. Somatic growth of preterm infants during skin-to-skin care versus traditional holding: a randomized, controlled trial. J Dev Behav Pediatr. 2003;24:163–8.,3939. Bier JA, Ferguson AE, Morales Y, Liebling JA, Archer D, Oh W, et al. Comparison of skin-to-skin contact with standard contact in low-birth-weight infants who are breast-fed. Arch Pediatr AdolescMed. 1996;150:1265–9.,4141. El-Farrash RA, Shinkar DM, Ragab DA, Salem RM, Saad WE, Farag AS, et al. Longer duration of kangaroo care improves neurobehavioral performance and feeding in preterm infants: a randomized controlled trial. Pediatr Res. 2020;87:683–8.,4242. Ludington-Hoe SM, Anderson GC, Swinth JY, Thompson C, Hadeed AJ. Randomized controlled trial of kangaroo care: cardiorespiratory and thermal effects on healthy preterm infants. Neonatal Netw. 2004;23:39–48.

Some studies reinforce the physiological benefits of the KMC, like the improvement in physiological parameters, such as increased oxygen saturation and temperature,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.,4343. Ludington-Hoe SM, Hosseini R, Torowicz DL. Skin-to-skin contact (Kangaroo Care) analgesia for preterm infant heel stick. AACN Clin Issues. 2005;16:373–87.,4444. Castral TC, Warnock F, Leite AM, Haas VJ, Scochi CG. The effects of skin-to-skin contact during acute pain in preterm newborns. Eur J Pain. 2008;12:464–71. improved weight gain,1515. Sharma D, Murki S, Oleti TP. Study comparing. Kangaroo Ward Care" with "Intermediate Intensive Care" for improving the growth outcome and cost effectiveness: randomized control trial. J Matern Fetal Neonatal Med. 2018;31:2986–93.,2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.,2828. Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3434. Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.,3535. Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8.,3737. Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42. reduced pain responses,4343. Ludington-Hoe SM, Hosseini R, Torowicz DL. Skin-to-skin contact (Kangaroo Care) analgesia for preterm infant heel stick. AACN Clin Issues. 2005;16:373–87.,4444. Castral TC, Warnock F, Leite AM, Haas VJ, Scochi CG. The effects of skin-to-skin contact during acute pain in preterm newborns. Eur J Pain. 2008;12:464–71.,4545. Cong X, Ludington-Hoe SM, Walsh S. Randomized crossover trial of kangaroo care to reduce biobehavioral pain responses in preterm infants: a pilot study. Biol Res Nurs. 2011;13:204–16.,4646. Mosayeb Z, Javidpou M, Rahmati M, Hagani H, Movahedian AH. The effect of Kangaroo Mother Care on pain from heel lance in preterm newborns admitted to neonatal intensive care unit: a crossover randomized clinical trial. J Compr Ped. 2014;5: e22214.,4747. Akcan E, Yiğit R, Atici A. The effect of kangaroo care on pain in premature infants during invasive procedures. Turk J Pediatr. 2009;51:14–8. reduced sepsis,2626. Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.,2929. Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.,3737. Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42. reduced apnea episodes,3737. Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42. and reduced hypothermia.2525. Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23. Studies have also shown an increase in the exclusive breastfeeding rate, one of the pillars of the KMC.99. Karimi FZ, Sadeghi R, Maleki-Saghooni N, Khadivzadeh T. The effect of mother-infant skin to skin contact on success and duration of first breastfeeding: a systematic review and metaanalysis. Taiwan J Obstet Gynecol. 2019;58:1–9.,1010. Ghojazadeh M, Hajebrahimi S, Pournaghi-Azar F, Mohseni M, Derakhshani N, Azami-Aghdash S. Effect of kangaroo mother care on successful breastfeeding: a systematic review and meta-analysis of randomised controlled trials. Rev Recent Clin Trials. 2019;14:31–40.,1111. Vaivada T, Gaffey MF, Bhutta ZA. Promoting early child development with interventions in health and nutrition: a systematic review. Pediatrics. 2017;140:e20164308.,1212. Sharma D, Farahbakhsh N, Sharma S, Sharma P, Sharma A. Role of kangaroo mother care in growth and breast feeding rates in very low birth weight (VLBW) neonates: a systematic review. J Matern Fetal Neonatal Med. 2019;32:129–42.,1313. Parker LA, Sullivan S, KruegerC, KelechiT, Mueller M. Strategies to increase milk volume in mothers of VLBW infants. MCN Am J Matern Child Nurs. 2013;38:385–90.,1414. Renfrew MJ, Dyson L, McCormick F, Misso K, Stenhouse E, King SE, et al. Breastfeeding promotion for infants in neonatal units: a systematic review. Child Care Health Dev. 2010;36:165–78. Weight gain and exclusive or almost exclusive breastfeeding were discharge criteria for most studies included in this systematic review, which explains the reduction in the length of hospital stay.

The meta-analysis performed involving all studies demonstrated the KMC effect in reducing the length of hospital stay compared to the conventional care. Although the heterogeneity is considerable, the reduction of 1 day and 18 hours (ranging from 3 days, 5 hours and 16 minutes to 6 hours and 43 minutes (-1.75 [-3.22 to -0.28]) in the hospitalization duration contributes to the reduction in the costs imposed on the family of infants,1515. Sharma D, Murki S, Oleti TP. Study comparing. Kangaroo Ward Care" with "Intermediate Intensive Care" for improving the growth outcome and cost effectiveness: randomized control trial. J Matern Fetal Neonatal Med. 2018;31:2986–93.,2727. Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8. and on the health system.1515. Sharma D, Murki S, Oleti TP. Study comparing. Kangaroo Ward Care" with "Intermediate Intensive Care" for improving the growth outcome and cost effectiveness: randomized control trial. J Matern Fetal Neonatal Med. 2018;31:2986–93.,1717. Sloan NL, Camacho LW, Rojas EP, Stern C. Kangaroo mother method: randomised controlled trial of an alternative method of care for stabilised low-birthweight infants. Maternidad Isidro Ayora Study Team. Lancet. 1994;344:782–5.,1818. Cattaneo A, Davanzo R, Worku B, SurjonoA, Echeverria M, Bedri A, et al. Kangaroo mother care for low birthweight infants: a randomized controlled trial in different settings. Acta Paediatr. 1998;87:976–85.

The statistical difference between the subgroups is due to the difference in the characteristics of the studies, especially regarding the discharge criteria. Although there was a statistical difference, the two subgroups showed a clinical reduction in the length of hospital stay.

The limitations found in the studies were mainly related to the risk of bias. Due to the intervention nature, it is not possible to blind the subjects and it is difficult to blind the professional who conducts the intervention. Another limitation refers to the discharge criteria used in the studies, which are believed to have generated a high heterogeneity.

The relevant aspects of this systematic review are the development of a sensitive search strategy, with a comprehensive search of the literature, and the quality screening and assessments performed by two independent authors. In addition, the included studies made it possible to perform a meta-analysis, where the hypothesis of effectiveness of the KMC in reducing the length of hospital stay of preterm and/ or LBW infants was established. There was no language limitation in the analysis of primary studies.

The findings in this systematic review show that managers and health professionals working in neonatology units should support and encourage actions to implement the KMC method in their facilities. Regarding the research implications, further studies are suggested to evaluate other benefits of the KMC method in addition to those already described in the literature to establish the ideal time of performance of KMC within the health units.

Conclusion

The KMC is a safe and low-cost intervention that has been shown to be effective in reducing the length of hospital stay of preterm and/or LBW infants.

References

  • 1.
    World Health Organization. Survive and thrive: transforming care for every small and sick newborn - key findings. Geneva: World Health Organization; 2018, [cited 2019 Abr 30]. Available from: http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/
    » http://www.who.int/maternal_child_adolescent/documents/care-small-sick-newborns-survive-thrive/en/
  • 2.
    Toma TS. From intuition to the public policies: the journey aimed to the incorporation of the Kangaroo Method (Método Canguru) for the care of low weight newborns. BIS Bol Inst Saúde. 2012;13:1231-8.
  • 3.
    Fundación Canguro y Departamento de Epidemiología Clínica y Bioestadística Facultad de Medicina – Pontificia Universidade Javeriana. Guías de práctica basadas en evidencia para la óptima utilización del Método Madre Canguro em el recién nacido pretérmino y/o de bajo peso al nacer. 2007 [cited 2019 Mar 19]. Available from: http://www.quenoosseparen.info/documen-tos/guias_evidencia.pdf
    » http://www.quenoosseparen.info/documen-tos/guias_evidencia.pdf
  • 4.
    Nyqvist KH, Expert Group of the International Network on Kangaroo Mother CareAnderson GC, Bergman N, Cattaneo A, Charpak N, et al. State of the art and recommendations. Kangaroo mother care: application in a high-tech environment. Acta Paediatr. 2010;99:812–9.
  • 5.
    Conde-Agudelo A, Belizán JM, Diaz-Rossello J. Kangaroo mother care to reduce morbidity and mortality in low birthweight infants. Cochrane Database Syst Rev. 2011(3):CD002771.
  • 6.
    Johnston C, Campbell-Yeo M, Disher T, Benoit B, Fernandes A, Streiner D, et al. Skin-to-skin care for procedural pain in neonates. Cochrane Database Syst Rev. 2017;2:CD008435.
  • 7.
    Pillai Riddell RR, Racine NM, Gennis HG, Turcotte K, Uman LS, Horton RE, et al. Non-pharmacological management of infant and young child procedural pain. Cochrane Database Syst Rev. 2015;2015:CD006275.
  • 8.
    Disher T, Benoit B, Johnston C, Campbell-Yeo M. Skin-to-skin contact for procedural pain in neonates: acceptability of novel systematic review synthesis methods and GRADEing of the evidence. J Adv Nurs. 2017;73:504–19.
  • 9.
    Karimi FZ, Sadeghi R, Maleki-Saghooni N, Khadivzadeh T. The effect of mother-infant skin to skin contact on success and duration of first breastfeeding: a systematic review and metaanalysis. Taiwan J Obstet Gynecol. 2019;58:1–9.
  • 10.
    Ghojazadeh M, Hajebrahimi S, Pournaghi-Azar F, Mohseni M, Derakhshani N, Azami-Aghdash S. Effect of kangaroo mother care on successful breastfeeding: a systematic review and meta-analysis of randomised controlled trials. Rev Recent Clin Trials. 2019;14:31–40.
  • 11.
    Vaivada T, Gaffey MF, Bhutta ZA. Promoting early child development with interventions in health and nutrition: a systematic review. Pediatrics. 2017;140:e20164308.
  • 12.
    Sharma D, Farahbakhsh N, Sharma S, Sharma P, Sharma A. Role of kangaroo mother care in growth and breast feeding rates in very low birth weight (VLBW) neonates: a systematic review. J Matern Fetal Neonatal Med. 2019;32:129–42.
  • 13.
    Parker LA, Sullivan S, KruegerC, KelechiT, Mueller M. Strategies to increase milk volume in mothers of VLBW infants. MCN Am J Matern Child Nurs. 2013;38:385–90.
  • 14.
    Renfrew MJ, Dyson L, McCormick F, Misso K, Stenhouse E, King SE, et al. Breastfeeding promotion for infants in neonatal units: a systematic review. Child Care Health Dev. 2010;36:165–78.
  • 15.
    Sharma D, Murki S, Oleti TP. Study comparing. Kangaroo Ward Care" with "Intermediate Intensive Care" for improving the growth outcome and cost effectiveness: randomized control trial. J Matern Fetal Neonatal Med. 2018;31:2986–93.
  • 16.
    Charpak N, Ruiz-Peláez JG, Figueroa CZ, Charpak Y. Kangaroo mother versus traditional care for newborn infants </=2000 Grams: a randomized, controlled trial. Pediatrics. 1997;100:682–8.
  • 17.
    Sloan NL, Camacho LW, Rojas EP, Stern C. Kangaroo mother method: randomised controlled trial of an alternative method of care for stabilised low-birthweight infants. Maternidad Isidro Ayora Study Team. Lancet. 1994;344:782–5.
  • 18.
    Cattaneo A, Davanzo R, Worku B, SurjonoA, Echeverria M, Bedri A, et al. Kangaroo mother care for low birthweight infants: a randomized controlled trial in different settings. Acta Paediatr. 1998;87:976–85.
  • 19.
    Covidence Systematic Review Software, Veritas Health Innovation, Melbourne, Australia. [Cited 2021 Mar 20]. Available from: http://www.covidence.org
    » http://www.covidence.org
  • 20.
    Higgins JP, Sterne JA, Savović J, Page MJ, Hróbjartsson A, Boutron I, et al. A revised tool for assessing risk of bias in randomized trials. In: Chandler J, McKenzie J, Boutron I, Welch V (editors). Cochrane methods. Cochrane Database Syst Rev; 2016;10:CD201601.
  • 21.
    Moher D, Liberati A, Tetzlaff J, Altman DG, Group PRISMA. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoSMed. 2009;6:e1000097.
  • 22.
    The Nordic Cochrane Centre, The Cochrane Collaboration. Review Manager (RevMan). Version 5.3. Conpenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration; 2014.
  • 23.
    Higgins JP, Tomas J. Cochrane handbook for systematic reviews of interventions. 2nd ed. Oxford: Wiley Blackwell; 2019.
  • 24.
    Tessier R, Cristo M, Velez S, Giron M, de Calume ZF, Ruiz-Palaez JG, et al. Kangaroo mother care and the bonding hypothesis. Pediatrics. 1998;102:e17.
  • 25.
    Acharya N, Singh RR, Bhatta NK, Pouldel P. Randomized control trial of kangaroo mother care in low birth weight babies at a tertiary level hospital. J Nepal Paediatr Soc. 2014;34:18–23.
  • 26.
    Ali SM, Sharma J, Sharma R, Alam S. Kangaroo mother care as compared to conventional care for low birth weight babies. DicleMed J Cilt. 2009;36:155–60.
  • 27.
    Kadam S, Binoy S, KanburW, Mondkar JA, Fernandez A. Feasibility of kangaroo mother care in Mumbai. Indian J Pediatr. 2005;72:35–8.
  • 28.
    Ramanathan K, Paul VK, Deorari AK, Taneja U, George G. Kangaroo mother care in very low birth weight infants. Indian J Pediatr. 2001;68:1019–23.
  • 29.
    Suman RP, Udani R, Nanavati R. Kangaroo mother care for low birth weight infants: a randomized controlled trial. Indian Pediatr. 2008;45:17–23.
  • 30.
    Gathwala G, Singh B, Balhara B. KMC facilitates mother baby attachment in low birth weight infants. Indian J Pediatr. 2008;75:43–7.
  • 31.
    Ghavane S, Murki S, Subramanian S, Gaddam P, Kandraju H, Thumalla S. Kangaroo mother care in kangaroo ward for improving the growth and breastfeeding outcomes when reaching term gestational age in very low birth weight infants. Acta Paediatr. 2012;101:e545–9.
  • 32.
    Boo NY, Jamli FM. Short duration of skin-to-skin contact: effects on growth and breastfeeding. J Paediatr Child Health. 2007;43:831–6.
  • 33.
    ChwoMJ, Anderson GC, Good M, Dowling DA, Shiau SH, Chu DM. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity. J Nurs Res. 2002;10:129–42.
  • 34.
    Lumbanraja SN. Influence of maternal factors on the successful outcome of kangaroo mother care in low birth-weight infants: a randomized controlled trial. J Neonatal Perinatal Med. 2016;9:385–92.
  • 35.
    Mwendwa AC, Musoke RN, Wamalwa DC. Impact of partial kangaroo mother care on growth rates and duration of hospital stay of low birth weight infants at the Kenyatta National Hospital, Nairobi. East Afr Med J. 2012;89:53–8.
  • 36.
    Santos EJ, Cunha M. Critical interpretation of statistical results of a meta-analysis: methodological strategies. Millenium. 2013;44:85–98.
  • 37.
    Kumbhojkar S, Mokase Y, Sarawade S. Kangaroo mother care (KMC): an alternative to conventional method of care for low birth weight babies. Int J Health Sci Res. 2016;6:36–42.
  • 38.
    Rojas MA, Kaplan M, Quevedo M, Sherwonit E, Foster L, Ehrenkranz RA, et al. Somatic growth of preterm infants during skin-to-skin care versus traditional holding: a randomized, controlled trial. J Dev Behav Pediatr. 2003;24:163–8.
  • 39.
    Bier JA, Ferguson AE, Morales Y, Liebling JA, Archer D, Oh W, et al. Comparison of skin-to-skin contact with standard contact in low-birth-weight infants who are breast-fed. Arch Pediatr AdolescMed. 1996;150:1265–9.
  • 40.
    Roberts KL, Paynter C, McEwan B. A comparison of kangaroo mother care and conventional cuddling care. Neonatal Netw. 2000;19:31–5.
  • 41.
    El-Farrash RA, Shinkar DM, Ragab DA, Salem RM, Saad WE, Farag AS, et al. Longer duration of kangaroo care improves neurobehavioral performance and feeding in preterm infants: a randomized controlled trial. Pediatr Res. 2020;87:683–8.
  • 42.
    Ludington-Hoe SM, Anderson GC, Swinth JY, Thompson C, Hadeed AJ. Randomized controlled trial of kangaroo care: cardiorespiratory and thermal effects on healthy preterm infants. Neonatal Netw. 2004;23:39–48.
  • 43.
    Ludington-Hoe SM, Hosseini R, Torowicz DL. Skin-to-skin contact (Kangaroo Care) analgesia for preterm infant heel stick. AACN Clin Issues. 2005;16:373–87.
  • 44.
    Castral TC, Warnock F, Leite AM, Haas VJ, Scochi CG. The effects of skin-to-skin contact during acute pain in preterm newborns. Eur J Pain. 2008;12:464–71.
  • 45.
    Cong X, Ludington-Hoe SM, Walsh S. Randomized crossover trial of kangaroo care to reduce biobehavioral pain responses in preterm infants: a pilot study. Biol Res Nurs. 2011;13:204–16.
  • 46.
    Mosayeb Z, Javidpou M, Rahmati M, Hagani H, Movahedian AH. The effect of Kangaroo Mother Care on pain from heel lance in preterm newborns admitted to neonatal intensive care unit: a crossover randomized clinical trial. J Compr Ped. 2014;5: e22214.
  • 47.
    Akcan E, Yiğit R, Atici A. The effect of kangaroo care on pain in premature infants during invasive procedures. Turk J Pediatr. 2009;51:14–8.

Publication Dates

  • Publication in this collection
    20 Apr 2022
  • Date of issue
    Mar-Apr 2022

History

  • Received
    13 Apr 2021
  • Accepted
    02 June 2021
  • Published
    16 July 2021
Sociedade Brasileira de Pediatria Av. Carlos Gomes, 328 cj. 304, 90480-000 Porto Alegre RS Brazil, Tel.: +55 51 3328-9520 - Porto Alegre - RS - Brazil
E-mail: jped@jped.com.br