Edwards AC, et al. - Using data from longitudinal population-wide Swedish medical, pharmacy, and criminal registries, the authors sought to elucidate the etiology of the association between pregnancy and reduced risk of alcohol use disorder. They performed a comparison of pregnant women born between 1975 and 1992 (N=322,029) with matched population controls, with female relatives discordant for pregnancy, and with pre- and postpregnancy periods within individuals. Observation revealed an inverse association between pregnancy and alcohol use disorder across all analyses. Pregnancy thus has a critical, and likely causal, motivational role in decreasing alcohol use disorder risk among women and, to a lesser extent, their partners. Results further enhance the knowledge regarding the relationship between pregnancy and alcohol use and illustrate that even a severe condition such as alcohol use disorder is subject to the protective effects of pregnancy.