Mental health and gestational weight gain: A comparison between Brazilian cohorts

Introduction: The mental health of pregnant women is critical as it influences both maternal and neonatal outcomes. This study investigates the association between maternal mental health and gestational weight gain (GWG) in two Brazilian cohorts conducted in different periods. Methods: The Jundiaí cohort (1997–2000) included 875 pregnant women, while the Araraquara cohort (2017–2024) evaluated mental health of 556 pregnant women from 2017 to 2019. Maternal mental health was assessed using the General Health Questionnaire (GHQ), the State-Trait Anxiety Inventory (STAI), and the Perceived Stress Scale (PSS) during the first, second, and third trimesters. GWG was categorized as adequate, insufficient, or excessive based on Institute of Medicine guidelines. Statistical analysis included bivariate tests (Kruskal-Wallis, chi-square, or Fisher’s exact test) and multinomial ordinal logistic regression to evaluate associations. Results: In the Jundiaí cohort, high stress levels in the first trimester were associated with lower odds of insufficient GWG (adjusted OR for second quartile: 0.36, 95% CI: 0.18–0.71). In the second trimester, high anxiety levels (TAI ≥ 40) were associated with higher odds of insufficient GWG (ORa: 1.76, 95% CI: 1.12–2.76). In the third trimester, high stress levels (PSS fourth quartile) were associated with higher odds of insufficient GWG (adjusted OR: 1.72, 95% CI: 1.02–2.91). In the Araraquara cohort, no significant associations between mental health and GWG were found. Conclusions: Our findings highlight the importance of incorporating psychosocial support in prenatal care to improve maternal and neonatal outcomes. Variations in socioeconomic and temporal contexts may influence the relationship between mental health and GWG. Future research should explore the underlying mechanisms and develop interventions tailored to different socioeconomic and temporal contexts.