Mechanical prosthetic heart valves (MPHV) in pregnancy are associated with a high risk of maternal and fetal morbidity and mortality

We read with interest the paper by Bhagra et al1 and wish to add further information from two recent publications which emphasise their key points that ‘pregnancy in women with mechanical heart valves is high risk’ and that ‘a multidisciplinary team approach to the management of pregnant women with Prosthetic Heart Valves is necessary to ensure optimal outcomes.’

A recent prospective observational national study of women in the UK with pregnancies between February 2013 and January 2015, estimated the incidence of mechanical prosthetic heart valves (MPHVs) in pregnancy to be 3.7 per 100 000 and described high rates of maternal mortality (9%), serious maternal morbidity (41%) and poor fetal outcomes (47% of the cohort and 35% of those reaching the third trimester).2 These complication rates are higher than previously described in the literature. This may be because the validated methodology resulted in less reporting bias; or because of variation...