Outcome of pregnancy in a contemporary cohort of adults with congenital heart disease-a 10-year, single-center experience.

Background: Pregnancy may be associated with adverse outcome in women with congenital heart disease (CHD). However, data regarding the outcome of pregnancy in women with CHD who receive care in cardiac-obstetric expert units are limited.

Methods: We retrospectively analyzed baseline characteristics and outcome of pregnancy in 67 females with CHD who received medical care in our tertiary center for 61 singleton and 6 twin pregnancies between 2009 and 2018.

Results: According to the modified World Health Organization (mWHO) risk scale for pregnancy, CHD lesions in 39 enrolled women (58%) were classified as mWHO class I or II, and in 28 females (42%) as mWHO class III or IV. Preterm births were more frequent in mWHO classes III or IV (P=0.003). Cardiac signs and complications occurred more often in mWHO classes III or IV than in women with cardiac lesions assigned to mWHO classes I or II (42.9% . 7.7%, P=0.002). N-terminal pro B-type natriuretic peptide (NT-proBNP) levels during pregnancy were higher in mWHO classes III or IV than in mWHO classes I or II (median 269.0 . 115.5 pg/mL, P=0.019). Presence of functional NYHA class III [odds ratio (OR) per standard deviation (SD) 8.8, 95% confidence interval (CI): 2.2-57.2, P=0.008] and mWHO classes III/IV (OR per SD 3.4, 95% CI: 1.2-9.9, P=0.018) prior to pregnancy were identified as independent predictors of adverse cardiac outcome of pregnancy.

Conclusions: Adverse cardiac events and preterm deliveries should be anticipated in pregnant women with CHD, especially in those with mWHO classes III or IV. Therefore, these pregnancies should be under close surveillance and managed in specialized, multidisciplinary tertiary referral centers. Preconception counseling including individualized risk assessment is strongly recommended in women with CHD.