Consanguineous Marriage and Early Pregnancy Loss in Rural to Peri-Urban India.

Background: Consanguineous marriage (CM) has been linked to spontaneous abortion (SAB), although studies have largely been cross-sectional and likely underestimated early loss. We aimed to determine the relationships between CM and SAB in a prospective pregnancy cohort study in Telangana State, India. Methods: Data from 661 participants aged 15-35 years in the Longitudinal Indian Family hEalth (LIFE) study actively followed for pregnancy and pregnancy loss were analyzed. SAB was classified as early (< 8) or late (8-22) weeks gestation. We used logistic regression to model the relationships between CM, defined by first-cousin marriage, and SAB, adjusted for maternal age. Results: Women in CM were at a modestly increased risk of any (ORadj 1.15, 95% CI 0.69, 1.91) and early (ORadj 2.03, 95% CI 0.85, 4.83) SAB compared to women in non-CM, although results were not statistically significant. There was no relationship between CM and late SAB. Conclusion: Among couples in southern India, there was a modest increase in early but not late SAB among CMs which may be explained by the expected influence of chromosomal abnormalities and lethal homozygous recessive disease on early loss. Pre- and Peri-marital Health Counseling that addresses this risk may be warranted. Supplementary Information: The online version contains supplementary material available at 10.1007/s13224-021-01498-7.