Objective: To compare the risks of pregnancy complications in women with repaired and unrepaired isolated ventricular septal defect (VSD).
Design: A retrospective multicentre study.
Setting: Tertiary centres in the Netherlands and Belgium.
Methods: Women were identified using two congenital heart disease registries. Eighty-eight women were identified who had experienced 202 pregnancies, including 46 miscarriages and nine terminations of pregnancy. Information on each completed pregnancy (n = 147; unrepaired VSD, n = 104; repaired VSD, n = 43) was obtained using medical records and telephone interviews. Data from the Generation R database (prospective cohort study; n = 9667) were used to determine the background risk (controls). Odds ratios and 95% CI were estimated using general estimation equation analysis adjusted for multiple pregnancies per woman, maternal age and parity status.
Main outcome measures: Adjusted odds ratios (AORs) for developing pregnancy complications in relation to corrective status.
Results: Pregnancies in women with an unrepaired VSD were associated with a higher risk of pre-eclampsia (AOR 4.59, 95% CI 2.01-10.5, P < 0.001) compared with controls. No differences were observed when comparing women with repaired VSD and controls. Pregnancies in women with repaired VSD were associated with a higher risk of premature labour (AOR 4.02, 95% CI 1.12-14.4, P = 0.03) and small-for-gestational-age (SGA) births (AOR 4.09, 95% CI 1.27-13.2, P = 0.02) compared with women with unrepaired VSD.
Conclusions: Women with unrepaired VSD are at increased risk of pre-eclampsia, which suggests that it is not a benign condition. In addition, women with repaired VSD are at increased risk of premature labour and SGA births compared with women with unrepaired VSD.