Incidence, prevalence, and mortality of maternal cardiac disease: a systematic review and meta-analysis

Background The estimated burden of maternal cardiac disease in studies varies between countries. This systematic review and meta-analysis aimed to estimate the incidence, prevalence, and mortality of maternal cardiac disease and its subtypes in high-income countries (HICs) and low-income and middle-income countries (LMICs). Methods A systematic literature review was conducted by searching MEDLINE, Embase, CINAHL, and Google Scholar for population-based and observational studies on maternal cardiac disease during pregnancy or up to 6 weeks postpartum, without age restriction, published between Jan 1, 2013, and April 30, 2025. The risk of bias was assessed. Meta-analysis of binomial data with hierarchical modelling was performed, and heterogeneity was assessed. The study was registered with PROSPERO (CRD42023487679). Findings The systematic review included 89 publications (100 datasets) using data from HICs and 25 (25 datasets) using data from LMICs. The pooled prevalence of maternal cardiac disease during pregnancy or at delivery was 0·54% (95% CI 0·26–4·95; I 2 =99·50%) in HICs and 2·34% (1·02–8·14; I 2 =97·75%) in LMICs. The most prevalent cardiac disease subtypes in HICs were arrhythmias (0·68% 0·30–2·84; I 2 =99·54%), congenital heart disease (0·21% 0·15–0·57; I 2 =98·85%), and valvular heart disease (0·16% 0·12–2·12; I 2 =99·94%). In LMICs, rheumatic heart disease showed the highest pooled prevalence (1·04% 0·44–3·95; I 2 =95·11%), followed by congenital heart disease (0·64% 0·31–1·93; I 2 =93·05%). The pooled maternal mortality rate due to cardiac disease during pregnancy or up to 6 weeks postpartum was 2 per 100 000 women giving birth (95% CI 2–3 per 100 000; I 2 =88·86%) in HICs. High heterogeneity was the main limitation, with different disease definitions and data sources being key sources of variation. Evidence from LMICs was less common than that in HICs and studies had a higher risk of bias due to single-centre designs, although most HICs data came from the USA and the UK, limiting the representativeness of the findings for other high-income settings. Interpretation Estimates of the prevalence, incidence, and mortality of maternal cardiac disease and subtypes are available for HICs and LMICs, but because of high variability between studies, the true burden remains uncertain. Further research using consistent disease definitions and comparable data sources is needed. More data from LMICs and a greater diversity of HICs are needed. Funding Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Science; National Institute for Health and Care Research; China Scholarship Council–CAMS Oxford Institute MD/PhD Scholarship.