Climate Variability Shapes Miscarriage, Stillbirth, and Abortion

Exposure to climate variability is associated with pregnancy termination, yet no prior study has distinguished between induced and spontaneous termination. This study links reproductive calendar data to high-resolution temperature and precipitation records (N = 308,035 pregnancies) to provide a novel, trimester-specific assessment of climate effects on miscarriage, stillbirth, and abortion in South Asia. I find that temperatures during conception and early gestation increase the likelihood of miscarriage and abortion, while dry conditions elevate miscarriage risk. These effects are comparable in magnitude to established sociodemographic predictors of adverse pregnancy outcomes. Once social stratification is considered, however, divergent patterns emerge. Increased years of schooling protect women from spontaneous termination associated with heat and drought, and abortion responses to precipitation shocks are concentrated among the most highly educated women. Together, these findings demonstrate that climate variability operates within existing social hierarchies, shaping both physiological vulnerability and unequal reproductive agency, and reinforcing stratified patterns of fertility and pregnancy loss.