To quantify the rate of cesarean section secondary to fetal distress in pregnancies complicated by growth restriction with and without abnormal fetal umbilical artery (UA) Doppler findings when compared to normal pregnancies.
Retrospective analysis of 297 pregnancies complicated by intrauterine growth restriction from 2009-2015 at two affiliate hospitals in the same large metropolitan area. All growth restricted fetuses with abnormal UA Doppler were identified (n=84) after exclusions for known aneuploidy, fetal demise, cardiac anomalies and missing delivery data. A cohort with growth restriction and normal UA Doppler (n=213) were selected in a 2:1 ratio. Information regarding demographic data, maternal comorbidities, neonatal outcomes, mode of delivery, and indication for cesarean section were collected from the medical record. Odds ratios for cesarean section, adjusted for gestational age using a multivariate logistic regression model, were calculated for both groups compared to all non-growth restricted deliveries at the main delivery institution in 2015.
There was a higher rate of cesarean section for fetal distress in growth restricted fetuses with abnormal Doppler when compared to normal Doppler (52.4% vs 17.4%; p=<0.0001). When compared to the non-growth restricted delivery population, there was an overall increased risk of cesarean section with both the normal Doppler group (OR 1.6; CI=1.2-2.1) and the abnormal Doppler group (OR 12.7; CI=5.8-28.1). There was a further increased risk when evaluating cesarean section for fetal distress in both normal (OR 3.7; CI=2.5-5.3) and abnormal (OR 16.6; CI=9.6-28.5) Doppler groups. A sub-group analysis of the normal Doppler group with oligohydramnios was found to have an increased rate of cesarean section (54.6% vs. 39.6%; p=0.07), but this was not statistically significant. Of patients that were eligible for induction, 76.2% (n=99) of the normal Doppler group and 35.0% (n=7) of the abnormal Doppler group had a successful vaginal delivery.
Fetal growth restriction confers an elevated risk of cesarean section for fetal distress, which is further increased in the presence of abnormal UA Doppler. However, there remains an acceptable rate of vaginal delivery in these groups and induction is a potential option for eligible patients.
© 2016 Published by Elsevier Inc.