Purpose: to evaluate the modifications due to premature rupture of the membranes of variables of the fetal biophysical profile, comparing them to the ones found in pregnant women with intact membranes. In the group with premature rupture of the membranes, the association of biophysical variables with the Apgar score at the first and fifth minutes and with the occurrence or not of clinical chorioamnionitis and neonatal infection was analyzed. Patients and Methods: in a prospective study, 112 fetal biophysical profiles were established in 60 pregnant women with premature rupture of the membranes at a period between the 28th and the 40th week of pregnancy, and only the last fetal biophysical profile was analyzed and compared to other 60 fetal biophysical profiles of pregnant women with gestational ages identical to the group of study and with intact membranes. Results: statistical analysis of the results revealed that the premature rupture of the membranes diminished the reactivity, not interfering with the body movements of the fetus. It also diminished the frequency of the respiratory movements of the fetus, not determining modifications of the fetal tonus, and considerably decreasing the amniotic fluid index. In terms of prediction of chorioamnionitis and neonatal infection, the fetal biophysical profile did not show any significant statistic validity; however, when the biophysical variables were present, the correlation with the absence of chorioamnionitis and neonatal infection was clearly shown. The result of the last fetal biophysical profile was strongly associated with the Apgar score at the 5th minute. Conclusion: the fetal biophysical profile should be used routinely in pregnant women with premature rupture of the membranes with the purpose of evaluating fetal vitality, and in order to detect those fetuses at a higher risk of infection, specially those with gestational ages of less than 34 weeks. Regarding those fetuses it is best to use a conservative approach.
Fetal vitality; Fetal biophysical profile; Premature rupture of the membranes
