Management of pregnancy complicated by hypertrophic obstructive cardiomyopathy.

We report our experiences with nine women suffering from hypertrophic obstructive cardiomyopathy who between them had 13 pregnancies, 10 of which were directly managed by us. Though at first we felt that the theoretical hazards of vaginal delivery indicated elective caesarean section, experience has convinced us that in the absence of an obstetrical contraindication these patients may be delivered vaginally provided a betaadrenergic blocking drug is administered during pregnancy and especially during labour, ergometrine is given at the end of the second stage, adequate supplies of cross-matched blood are available, and prophylaxis against infective endocarditis is administered. We have found no evidence of any adverse effects of either propranolol or pronethalol on the foetus.