After peripartum cardiomyopathy, a recovered heart lowers the risk of death in the next pregnancy but not the risk of relapse

The edition in brief

Women with previous peripartum cardiomyopathy (PPCM) whose ejection fraction had recovered to 50% or more before the next pregnancy had lower maternal mortality than those who had not recovered (1.7% vs 10.9%; RR 0.27, 95% CI 0.09–0.87), but relapse was about as common in both groups (RR 0.77, 0.50–1.19). The evidence is six cohorts and 266 women, so the estimates are imprecise. Recovery is reassuring; it does not remove the need for cardio-obstetric care. A meta-analysis of 2.1 million pregnancies found maternal anaemia associated with preterm birth (OR 1.28, 1.20–1.36), most strongly when anaemia was present in the third trimester (OR 1.65, 1.42–1.91). Heterogeneity was very high and publication bias likely, and the studies were observational, so the link is not proof that correcting anaemia prevents preterm birth. It is still a reason to recheck haemoglobin late in pregnancy. In a randomised trial of 626 pregnant women with HIV, about half developed raised blood pressure by 50 weeks postpartum, with no significant difference between dolutegravir- and efavirenz-based regimens; each extra 5 kg of weight was associated with an 8–17% higher hazard. A post hoc analysis of the ASPIRIN trial in low-resource settings found the effect of low-dose aspirin on preterm birth did not change with the week it was started (6–13 weeks) or with adherence. The pearl: repeat the haemoglobin in the third trimester rather than relying on the booking value.