Effect of postpartum depression and role of infant feeding practices on relative weight of child at 1 and 3 years of age

Background Childhood obesity has increased and is considered one of the most serious public health challenges of the 21st century globally, and may be exacerbated by postpartum depression (PPD). The purpose of this study was to examine the association between PPD at 1(st) and 6(th) month postpartum, infant feeding practices, and body mass index (BMI) z-score of the child at one and three years of age. Methods This study used data from an ongoing prospective maternal-child birth cohort performed at the National Center for Child Health and Development (NCCHD) in suburban Tokyo, Japan with the period of recruitment from May 13, 2010 to November 28, 2013. Out of 2,309 total number of mothers, 1,279 mother-child dyads were assessed in the study. We performed multivariable linear regression analysis to examine the association between PPD and child's BMI z-score stratified by the child's age at 1 year and 3 years of age. Results The prevalence of PPD at 1 month postpartum (17%) was found to be higher than at 6 months (12%). In multivariable linear regression analysis we observed that children at 3 years who had mothers with PPD at 6 months had, on average, a BMI z-score 0.25 higher than children of mothers who did not have PPD at 6 months (ss coefficient 0.25, 95% CI [0.04 to 0.46], p value 0.02), holding all other covariates constant. Also, initiation of weaning food when child is at six months of age was associated with higher BMI z-score of the child at 3 years after adjusting for all covariates (ss coefficient = 0.18, 95% CI [0.03 to 0.34], p-value < 0.05). Conclusion The significant association between PPD at 6 months and child's BMI z-score at 3 years of age, in conjunction with birth trends and high prevalence of PPD, can add to the body of evidence that there is need for multiple assessment across the first postpartum year to rule out PPD as early screening and early interventions may benefit both maternal health and child development outcomes. These findings can indicate the need for establishing support systems for care-giving activities for mothers with PPD.