249 Labor length and adverse cardiac outcomes among women with congenital heart disease

Abstract

Women with congenital heart disease (CHD) are at high risk for peripartum morbidity, yet data is limited on the impact of labor on morbidity. Our objective was to evaluate whether exposure to labor and duration of labor were associated with rates of adverse maternal cardiac outcomes among women with CHD. This was a secondary analysis of a retrospective cohort study of women ≥18 years with CHD who received prenatal care and delivered at the Hospital of the University of Pennsylvania between 1998-2014 with a singleton gestation. Only the first pregnancy was counted for women who delivered more than once. Pregnancies that ended in termination or loss <24 weeks gestation were excluded. A composite adverse maternal cardiac outcome included any cardiac event during pregnancy or <6 months post-partum (specific outcomes listed in Figure), compared among women who did and did not labor. 168 women were included; 34 (20.2%) underwent planned cesarean delivery (CD) without labor and 134 (79.8%) labored. The overall rate of adverse cardiac outcome was 20.2%; 23.5% in the planned CD group and 19.4% in those that labored, regardless of mode of delivery (p=0.6). The most common adverse events were heart failure (13.7%) and arrhythmia (7.7%). As shown in the Figure, women who delivered in <24 hours (regardless of mode of delivery) had a lower rate of adverse cardiac outcome than those that delivered after ≥24 hours of labor, though not statistically significant (p=0.06). When adjusting for confounders including NYHA class, systemic ventricular dysfunction, and mode of delivery, women with labor length ≥15 hours had a 3.7-fold higher odds of adverse cardiac outcome (aOR 3.7 [1.1-12.9]). In this retrospective cohort of women with CHD, exposure to labor was not associated with an increased risk of adverse cardiac outcome. However, among those who labored, longer labor was associated with an increased risk, regardless of mode of delivery. Attention should be paid to the duration of labor in women with CHD, as achieving a vaginal delivery does not mitigate the risks of prolonged labor.View Large Image Figure ViewerDownload Hi-res image Download (PPT)