Studying or mothering?: the effect of legal interruption of pregnancy on female school dropout in Mexico

Abstract

This thesis estimates the causal effect of abortion legalization (Interrupción Legal del Embarazo, ILE) on female school dropout rates in Mexico, exploiting the staggered adoption of legalization across states beginning with Mexico City in 2007. Using administrative enrollment data from the Secretariat of Public Education (Formato 911) for upper secondary education and from ANUIES for higher education, covering school years 2003–2004 through 2024–2025, the analysis employs the Callaway and Sant’Anna (2021) difference-in-differences estimator to recover group-time average treatment effects disaggregated by single year of age. At the university level, legalization is associated with a statistically significant reduction in female dropout that grows monotonically with age: from non-significant effects at 17–18 years to reductions of 5.2–6.1 cases per 100 enrolled women at 20–22 (p < 0.01), a deepening long-run effect of −7.07 at age 24 (p < 0.05), and a peak of −14.12 at 25–29 years (p < 0.01). No systematic effect is detected at the upper secondary level. This divergence — significant and growing effects only at the university stage — points to a lagged educational dividend: the reproductive options enabled by legalization during adolescence do not reduce dropout at the level where those choices first become available, but rather yield their returns downstream, as cumulative exposure to legal abortion reshapes fertility planning throughout the university years. A complementary mechanism analysis using synthetic control difference-in-differences on INEGI birth registration data lends support to this interpretation: legalization in Mexico City is associated with a significant reduction of 1,400 births per 100,000 women aged 15–19 (p = 0.007), while no significant fertility effects are detected in later-adopting states — evidence that legal change without adequate institutional infrastructure is insufficient to alter reproductive behavior. Crucially, the adolescent fertility decline does not translate into contemporaneous dropout reductions at the upper secondary level; instead, the monotonic age gradient at the university stage suggests that the educational returns of lower adolescent fertility materialize over a longer horizon, as women who avoided an early unplanned pregnancy persist through higher education at greater rates. These findings contribute the first causal evidence on the effect of abortion legalization on educational outcomes in Mexico and carry direct implications for public policy: expanding effective access to the ILE — through clinical infrastructure, trained personnel, and destigmatization — constitutes a measurable investment in female human capital.