Nicotine Dependence and Postpartum Depression: A Multicenter Research Network Study.

Postpartum depression was associated with ND5y in the unmatched sample analysis, but not in the matched sample analysis. As a potential mechanism is unknown, it is possible that some of the matched variables have a shared mechanism with post-partum depression and matching may have masked the true relationship. Therefore, both the unmatched and propensity matched analyses are presented as both have important relevance and may spur future research with non-clinical-based data.