Risk of complications during pregnancy in women with congenital aortic stenosis

Background Pregnancy in women with congenital aortic stenosis (AS) is associated with increased cardiac complications. Data on non-cardiac complications are limited, and this information is crucial for prenatal counselling and perinatal care. The aim of this study was to present the maternal and perinatal outcome of pregnancy in women with congenital AS. Methods By review of the Dutch CONCOR national registry and a local Belgian tertiary care centre database, 35 women with congenital AS with a history of completed pregnancy before aortic valve replacement were enrolled in this study. Medical history and maternal and perinatal outcome were determined. Results Thirty-five women had 58 pregnancies resulting in 53 successful pregnancies, three miscarriages, and two abortions. The most serious cardiac complications were heart failure (n = 2, 3.8%) and atrial arrhythmia (n = 3, 5.7%). Although cardiac complications were present (9.4%), obstetric (22.6%) and perinatal (24.5%) complications were observed more often. A total of six pregnancies (11.3%) were complicated by hypertension-related disorders, including one case of eclampsia. Furthermore, 7 premature births (13.2%) and 7 small-for-gestational-age births (13.2%) were encountered. Pregnancy in women with severe AS was characterized by an increased incidence of heart failure and premature labour, and shorter pregnancy duration. Older women (> 30 years) were at increased risk of perinatal events (odds ratio 4.38, 95% confidence interval 1.02 to 18.81). Conclusions Pregnancy is generally well tolerated in women with congenital AS. Importantly, an excess of obstetric and perinatal complications was found, requiring more meticulous attention.