Miscarriage and stillbirth in relation to risk of cardiovascular diseases: A systematic review and meta-analysis

Introduction The relationship between pregnancy loss and the risk of cardiovascular diseases (CVDs) remains a matter of debate. Our intention in conducting this meta-analysis was to analyze the relationship between miscarriage and stillbirth and risk of CVDs. Methods PubMed, Embase, and Web of Science were systematically searched up to May 30, 2023 for all relevant studies. The random-effects model was applied to estimate the pooled relative risks (RRs) and 95% confidence intervals (95% CIs). We evaluated RR estimates for the risk of CVDs with each additional miscarriage and stillbirth through generalized least squares regression. Results Twenty-three articles were incorporated into the meta-analysis. For women with a history of miscarriage, the pooled RRs for the risk of total CVDs, coronary heart disease (CHD), stroke, and total CVD deaths were 1.16 (95 % CI 1.10–1.22), 1.26 (1.12–1.41), 1.13 (1.03–1.24), and 1.20 (1.01–1.42), respectively. For women with a history of stillbirth, the pooled RRs for the risk of total CVDs, CHD, stroke, and total CVD deaths were 1.60 (1.34–1.89), 1.30 (1.12–1.50), 1.37 (1.06–1.78), and 1.95 (1.05–3.63), respectively. With each additional miscarriage, the risk increased for total CVDs (1.08, 1.04–1.13), CHD (1.08, 1.04–1.13), and stroke (1.05, 1.00–1.10). With each additional stillbirth, the risk increased for total CVDs (1.11, 1.03–1.21) and CHD (1.13, 1.07–1.19). Conclusion This meta-analysis indicates that both miscarriages and stillbirths are related to a higher risk of total CVDs, CHD, stroke, and total CVD deaths. The risk of total CVDs and CHD increased with the number of miscarriages or stillbirths.