Secular trends in pregnancy rates, delivery outcomes, and related health care utilization among women with congenital heart disease

Background: The number of women with congenital heart disease (CHD) of reproductive age is increasing, yet a description of trends in pregnancy and delivery outcomes in this population is lacking.

Objective: To assess secular trends in pregnancy rates, delivery outcomes, and related health care utilization in the adult female CHD population in Quebec, Canada.

Methods: The Quebec CHD database was used to construct a cohort with all women with CHD aged 18-45 years between 1992 and 2004. Pregnancy and delivery rates were determined yearly and compared to the general population. Secular trends in pregnancy and delivery rates were assessed with linear regression. The cesarean delivery rate in the CHD population was compared to the general population. Predictors of cesarean section were determined with multivariable logistic regression. Cox regression, adjusted for comorbidities, was used to analyze the impact of cesarean sections on 1-year health care use following delivery.

Results: About 14 878 women were included. A total of 10 809 pregnancies were identified in 5641 women, of whom 4551 (80%) and 2528 (45%) experienced at least one delivery and/or abortion, respectively. Absolute yearly numbers and rates of pregnancies and deliveries increased during the study period (P < .05). The increment in cesarean section rates was more pronounced among women with CHD than among the general population. Gestational diabetes (OR 1.50, 95% CI [1.13, 1.99]), gestational hypertension (OR 1.81, 95% CI [1.27, 2.57]), and preeclampsia (OR 1.59, 95% CI [1.11, 2.8]) were independent predictors of cesarean delivery. Cesarean sections were associated with postpartum cardiac-hospitalization within 1 year following delivery (HR = 2.35, 95% CI [1.05, 5.28]).

Conclusions: Yearly numbers and rates of pregnancies and deliveries in adult females with CHD rose significantly during the study period. Cesarean sections led to increased health care utilization. Further research is required to determine causes of high cesarean section rates in this patient population.