Objective To investigate the prevalence, characteristics and maternal and perinatal outcomes of pregnancies complicated by heart disease.

Design Prospective single-centre registry.

Setting Tertiary care teaching hospital in eastern Nepal.

Patients Pregnant women presenting to the antenatal clinic and/or labour room between 1 March 2012 and 31 March 2013.

Main outcome measures Prevalence, characteristics, and maternal and perinatal outcomes of pregnancies complicated by heart disease.

Results Fifty-three out of 9463 pregnancies (0.6%) were complicated by cardiac disease. Proportions of acquired, congenital and arrhythmic heart disease amounted to 89%, 9% and 2%, respectively. Rheumatic heart disease (RHD) was the most frequent cardiac disease complicating pregnancy (n=47). Among 45 women with RHD continuing pregnancy until delivery, 30 (67%) were primigravidae. The predominant valvular pathology was mitral stenosis (62%), followed by mitral regurgitation (21%) and aortic regurgitation (13%). Twenty women (44%) underwent elective or emergency caesarean section. Maternal and fetal/perinatal mortality of pregnancies complicated by RHD amounted to 4% and 16%, respectively. New York Heart Association (NYHA) functional class III or class IV (HR 6.0, 95% CI 1.2 to 29.1, p=0.026), pulmonary hypertension (HR 9.1, 95% CI 1.6 to 51.5, p=0.012) and severe mitral stenosis (HR 7.0, 95% CI 1.4 to 34.4, p=0.017) were identified as predictors of maternal or fetal/perinatal mortality in an univariate analysis.

Conclusions Rheumatic mitral stenosis was the most frequent heart disease complicating pregnancy in a consecutive cohort from a teaching hospital in Nepal. Exercise intolerance, pulmonary hypertension and severe mitral stenosis were identified as predictors of maternal or fetal/perinatal mortality.