Explaining third birth patterns in India: causal effects of sibling sex composition

This paper analyzes the implications of son preference on birth spacing intervals in India. Sibling sex composition provides a credible source of exogenous variation in the Indian context for births on or before 1990, as sex screening became widespread only after the 1990 economic reforms. I use the sibling sex composition of the first two children to capture its impact on the third birth interval. My analysis shows that, on average, families with two sons face an 8% lower hazard of a third birth relative to families with two daughters. Moreover, I find three channels of heterogeneity: religion, mother’s age, and state of residence. Respondents from diverse religious groups respond differently to the sibling composition of the first two births regarding their likelihood of riskier births for the third interval. Moreover, older mothers with at least one son are less likely to have a shorter third birth interval than younger cohorts of mothers. Finally, the respondent’s state of residence also drives some heterogeneity, with mothers from non-southern states less likely to have a riskier third birth interval once they have had at least one son among the first two births.