Obstetric outcome of 6346 pregnancies with infants affected by congenital heart defects

To evaluate whether pregnancies with infants affected by congenital heart defects are associated with adverse obstetric and perinatal outcome.

In a prospective population-based cohort study from Sweden (1992-2001), 6346 singleton pregnancies with infants affected by congenital heart defects were, after suitable adjustments, compared to all delivered women.

The prevalence of cardiovascular defects was 9.1 per 1000 births. Among them, mothers of 6346 infants (71%) had information on maternal smoking habits and maternal height and weight in early pregnancy that enabled the calculation of BMI. All cases with known chromosomal abnormalities and/or maternal pre-existing diabetes were excluded. Eighty-four percent (n=5338) had an isolated cardiovascular defect. Severe types occurred in 21.7% (n=1378). In the group of pregnancies with infants affected by congenital heart defects as compared to all delivered women, there was an increased risk of the following outcomes (adjusted OR (95%CI)): pre-eclampsia (1.21 (1.06-1.37)), cesarean section (1.91 (1.79-2.03)), instrumental delivery (1.21 (1.10-1.34)), pre-term delivery (2.58 (2.39-2.79)), small-for gestational age (1.96 (1.77-2.16)), meconium aspiration (1.51 (1.28-1.77)), and fetal distress (1.38 (1.17-1.63)).

Pregnancies with infants affected by congenital heart defects are associated with several obstetric and neonatal complications.