We provide empirical evidence on the impact of raising the minimum age of marriage to 18 years old on child marriage, early motherhood, and school enrollment in Mexico. Using a difference-in-differences model that takes advantage of the staggered adoption of this reform across states, we show that banning child marriage leads to a large and statistically significant reduction in the number of registered child marriages. However, we find no effect on school attendance or early fertility rates. We provide evidence that the mechanism behind these results is the substitution of formal marriage for informal unions. These findings suggest that when informal unions are a viable option for young couples, raising the minimum age of marriage is not enough to prevent early unions and their negative consequences.

中文翻译：

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你以后会嫁给我吗？墨西哥的结婚年龄法和童婚

我们提供了关于将最低结婚年龄提高到 18 岁对墨西哥童婚、早孕和入学率的影响的经验证据。使用差异中的差异模型，利用跨州交错采用的这项改革，我们表明禁止童婚会导致登记的童婚数量在统计上显着减少。然而，我们发现对上学率或早期生育率没有影响。我们提供证据表明这些结果背后的机制是正式婚姻取代非正式结合。这些调查结果表明，当非正式结合是年轻夫妇的可行选择时，提高最低结婚年龄并不足以防止过早结合及其负面后果。