Neonatal outcomes in fetuses with cardiac anomalies and the impact of delivery route.

BACKGROUND

Congenital fetal cardiac anomalies compromise the most common group of fetal structural anomalies. Several previous reports analyzed all types of fetal cardiac anomalies together without individualized neonatal morbidity outcomes based on cardiac defect. Mode of delivery in cases of fetal cardiac anomalies varies greatly as optimal mode of delivery in these complex cases is unknown.

OBJECTIVE

We sought to determine rates of neonatal outcomes for fetal cardiac anomalies and examine the role of attempted route of delivery on neonatal morbidity.

STUDY DESIGN

Gravidas with fetal cardiac anomalies and delivery >34 weeks, excluding stillbirths and aneuploidies (n = 2166 neonates, n = 2701 cardiac anomalies), were analyzed from the Consortium on Safe Labor, a retrospective cohort study of electronic medical records. Cardiac anomalies were determined using International Classification of Diseases, Ninth Revision codes and organized based on morphology. Neonates were assigned to each cardiac anomaly classification based on the most severe cardiac defect present. Neonatal outcomes were determined for each fetal cardiac anomaly. Composite neonatal morbidity (serious respiratory morbidity, sepsis, birth trauma, hypoxic ischemic encephalopathy, and neonatal death) was compared between attempted vaginal delivery and planned cesarean delivery for prenatal and postnatal diagnosis. We used multivariate logistic regression to calculate adjusted odds ratio for composite neonatal morbidity controlling for race, parity, body mass index, insurance, gestational age, maternal disease, single or multiple anomalies, and maternal drug use.

RESULTS

Most cardiac anomalies were diagnosed postnatally except hypoplastic left heart syndrome, which had a higher prenatal than postnatal detection rate. Neonatal death occurred in 8.4% of 107 neonates with conotruncal defects. Serious respiratory morbidity occurred in 54.2% of 83 neonates with left ventricular outflow tract defects. Overall, 76.3% of pregnancies with fetal cardiac anomalies underwent attempted vaginal delivery. Among patients who underwent attempted vaginal delivery, 66.1% had a successful vaginal delivery. Women with a fetal cardiac anomaly diagnosed prenatally were more likely to have a planned cesarean delivery than women with a postnatal diagnosis (31.7 vs 22.8%; P < .001). Planned cesarean delivery compared to attempted vaginal delivery was not associated with decreased composite neonatal morbidity for all prenatally diagnosed (adjusted odds ratio, 1.67; 95% confidence interval, 0.85-3.30) or postnatally diagnosed (adjusted odds ratio, 0.99; 95% confidence interval, 0.77-1.27) cardiac anomalies.

CONCLUSION

Most fetal cardiac anomalies were diagnosed postnatally and associated with increased rates of neonatal morbidity. Planned cesarean delivery for prenatally diagnosed cardiac anomalies was not associated with less neonatal morbidity.