Fetal major anomalies and related maternal, obstetrical, and neonatal outcomes

Purpose: To examine maternal, obstetrical, and neonatal outcomes of pregnancies complicated by major fetal anomalies. Methods: A 10 year retrospective cohort study at a tertiary university hospital compared maternal and obstetrical outcomes between women with singleton pregnancies complicated by major fetal anomalies, and a control group with non-anomalous fetuses. Results: For the study compared to the control group, the median gestational age at delivery was lower: 37.0 vs. 39.4 weeks (p < 0.001); and the preterm delivery rates were higher, both at < 37 weeks (46.2 vs. 6.2%, p < 0.001) and < 32 weeks (15.4 vs. 1.2%, p < 0.001). For the study compared to the control group, the placental abruption rate was higher (6.8 vs. 0.9%, p = 0.002); 87.5 vs. 100% occurred before labor. For the respective groups, the mean gestational ages at abruption were 32.8 ± 1.3 and 39.9 ± 1.7 weeks (p = 0.024); and cesarean section and postpartum hemorrhage rates were: 53.8 vs. 28.3% (p < 0.001) and 11.3 vs. 2.8% (p = 0.001), respectively. For the respective groups, hypertensive disorders of pregnancy rates were 9.5 vs. 2.1% (p = 0.004), stillbirth rates were 17.1 vs. 0.3% (p < 0.001), and neonatal death rates 12.5 vs. 0.0% (p < 0.001). Major fetal anomalies were found to be associated with adverse maternal outcomes (OR = 2.47, 95% CI 1.50–4.09, p < 0.001). Polyhydramnios was identified as an independent risk factor in a multivariate analysis that adjusted for fetal anomalies, conception by IVF, and primiparity for adverse maternal outcomes (OR = 4.7, 95% CI 1.7–13.6, p < 0.001). Conclusions: Pregnancies with major fetal anomalies should be treated as high-risk due to the increased likelihood of adverse maternal and neonatal outcomes.