Obstetric outcomes in pregnant women with congenital heart disease

Background: Predictors of adverse maternal and neonatal outcomes in pregnant women with congenital heart disease (CHD) have been described, but not for obstetrical outcomes. The primary aim of this study was to determine what risk factors predict sustaining adverse obstetric events in pregnant women with CHD. In addition, a secondary aim was to assess the impact of avoiding Valsalva on obstetrical outcomes, an intervention commonly recommended, but never studied.

Methods: A retrospective cohort study examined outcomes in women with CHD who delivered between 1998 and 2005. We examined baseline cardiac characteristics in a multivariate logistic regression model to assess which were associated with adverse obstetric events. We also compared outcomes of women who avoided Valsalva versus those who were allowed to Valsalva.

Results: The study included 65 women with 112 pregnancies. An adverse obstetric event occurred in 32.6% (n=32) of ongoing pregnancies, the most common being preterm delivery (n=19), post-partum hemorrhage (n=13), and preterm premature rupture of membranes (n=9). There were no independent predictors for sustaining an adverse obstetric event. Women who avoided Valsalva had increased rates of post-partum hemorrhage and 3rd/4th degree lacerations.

Conclusions: Although one-third of pregnancies were associated with an adverse obstetric outcome, these events could not be predicted by baseline hemodynamic characteristics. The routine practice of avoiding Valsalva may be associated with high rates of post-partum hemorrhage and 3rd/4th degree lacerations.