Risk and timing of miscarriage and stillbirth in five low- and middle-income countries: evidence from longitudinal cohort studies

Background: Pregnancy loss, including miscarriage and stillbirth, is a major public health issue with major physical and psychological consequences for pregnant women. Prevalence estimates in low resource settings remain scarce due to the lack of adequate data. This study assessed the prevalence, timing, and maternal characteristics associated with stillbirth and miscarriage using novel longitudinal data collected in five low and middle-income countries (LMICs). Methods and Findings: We analyzed longitudinal data from 5755 pregnant women in Ethiopia, India, Kenya, South Africa, and Cote d'Ivoire. Women were enrolled during pregnancy and followed through delivery. Gestation-specific and cumulative risks of miscarriage and stillbirth were estimated using competing-risks survival analysis, adjusting for timing of enrollment. We examined associations with maternal age, education, wealth, and country using Fine and Gray sub-distribution hazard models. Among pregnancies surviving to 8 weeks, the cumulative risk of pregnancy loss by 28 weeks was 84 per 1,000 pregnancies (95% CI: 69 to 100) and from 28 to 44 weeks the risk was 19 per 1,000 (15 to 24), resulting in a total pregnancy loss risk after 8 weeks of gestation of 103 per 1,000 (88 to 119). Risks were highest in Cote d'Ivoire and lowest in South Africa. Losses peaked between 8 and 6 weeks of gestation, with a secondary rise after 36 weeks. Women aged above 35 years had higher loss risk (HR 1.78, 95% CI: 1.27 to 2.48), whereas wealth and education showed no consistent association. Conclusions: Pregnancy loss remains common across LMICs, with significant risk in both early and late gestation. Conventional estimates that do not account for delayed enrollment underestimate miscarriage rates. Enhanced surveillance and targeted interventions throughout pregnancy, especially during early gestation, are essential to reduce preventable fetal losses and meet associated global goals.