[The perinatal factors associated with the development of neonatal RDS in cases of placenta previa].

Sixty-two cases of preterm placenta previa were managed in our hospital since September, 1979 through August, 1983. These were reviewed and analysed retrospectively for the perinatal factors in terms of the development of respiratory distress syndrome (RDS). Conservative management was employed in 56 cases (90%), which consisted of antepartum blood transfusion (7 cases: 11.3%), tocolysis for inhibition of premature labor (37 cases: 59.7%), and prenatal steroid administration (8 cases: 12.9%). Nineteen cases (31%) were delivered from 28 to 33 weeks, 20 cases (32%) from 34 to 36 weeks, and 23 cases (37%) after 37 weeks. When regular uterine contractions occurred at less than 10 minute intervals at the initiation of tocolysis, the majority of the cases had to be delivered within 7 days or less. Ten of the 39 preterm neonates in this study developed clinical RDS. All of these were delivered at between 28 and 33 weeks, associated with neonatal asphyxia. Three perinatal factors were significantly associated with the development of clinical RDS in comparison with the control group of non-RDS preterm neonates. These were neonatal asphyxia, maternal bleeding (greater than 500 ml) and no prenatal steroid administration.