Maternal history of childhood maltreatment and pregnancy weight outcomes.

Background: Childhood maltreatment is associated with elevated adult weight. It is unclear whether this association extends to pregnancy, a critical window for the development of obesity.

Methods: We examined associations of childhood maltreatment histories with pre-pregnancy BMI and gestational weight gain among women who had participated for >20 years in a longitudinal cohort.At age 26-35 participants reported childhood maltreatment (physical, sexual, and emotional abuse; emotional neglect) and, 5 years later, about pre-pregnancy weight and gestational weight gain for previous pregnancies (n=656). Modified Poisson regression models were used to estimate associations of maltreatment history with pre-pregnancy BMI and gestational weight gain z-scores, adjusting for sociodemographics. We used Multivariate Imputation by Chained Equations to adjust outcome measures for misclassification using data from an internal validation study.

Results: Before misclassification adjustment, results indicated a higher risk of pre-pregnancy BMI ≥30 kg/m2 in women with certain types of maltreatment (e.g., emotional abuse RR=2.4; 95% CI: 1.5, 3.7) compared with women without that maltreatment type. After misclassification adjustment, estimates were attenuated but still modestly elevated (e.g., emotional abuse RR=1.7; 95% CI: 1.1, 2.7). Misclassification-adjusted estimates for maltreatment associations with gestational weight gain z-scores were close to the null and imprecise.

Conclusions: Findings suggest an association of maltreatment with pre-pregnancy BMI ≥30 kg/m2 but not with high gestational weight gain. Results suggest a potential need for equitable interventions that can support all women, including those with maltreatment histories, as they enter pregnancy.