Increased cesarean section rate and premature birth according to modified WHO maternal cardiovascular risk in pregnant women with congenital heart disease

BACKGROUND: During pregnancy and delivery, hemodynamics are altered and complex congenital heart disease has been associated with adverse maternal and neonatal outcomes. We sought to investigate pregnancy outcome and complications in relation to complexity of heart condition. MATERIALS AND METHODS: We studied women with ACHD discussed at multidisciplinary conferences at Lund University Hospital March 2009-May 2021. We studied 149 pregnancies in 101 women. We scored each woman retrospectively according to the modified World Health Organization (mWHO) risk classification and included patients in risk class I (n = 36, 24.1%), II (n = 43, 28.9%), II-III (n = 43, 28.9%), III (n = 24, 16.1%) and IV (n = 3, 2.0%). RESULTS: Women with mWHO class ≥III underwent cesarean section more often than women in less complex mWHO classes, (OR, 5.1; 95% CI, 2.0–12.5; p<0.001). The odds of premature delivery were significantly higher among pregnant women with mWHO class ≥III (OR, 6.7; 95% CI, 2.6–17.4; p<0.001). We found no difference in incidence of preeclampsia, gestational hypertension, gestational diabetes, hemorrhage >1000 ml or cardiac defect in the neonate depending on WHO-class. Women in mWHO classes III-IV had a higher rate of fetal growth restriction (FGR) compared to women in mWHO classes I, II, II-III (p<0.007). CONCLUSIONS: Our findings indicate that women with more complex heart disease (mWHO classes III or IV) tend to have a higher rate of cesarean section, premature birth and FGR.