Prevalence and Predictors of Substantial Postpartum Weight Retention Among Participants of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) in Southern California.

Purpose: Identify the prevalence and predictors of substantial postpartum weight retention (SPPWR) among WIC mothers in Southern California during their first postpartum year.

Design: Secondary data analysis.

Setting: The 2020 Los Angeles County WIC Survey.

Subjects: Mothers of children up to 1-year-old (N = 1019).

Measures: Outcome variable: SPPWR (≥5 kg above pre-pregnancy weight). Predictors: child's age, mother's age, race, education, employment status since having child, healthcare coverage, food insecurity, depressed mood, instrumental support, emotional support, spouse's participation in child's life, gestational weight gain (GWG), pre-pregnancy BMI, any breastfeeding, and gestational diabetes.

Analysis: Weighted descriptive statistics and binary logistic regression.

Results: The prevalence of SPPWR was 31%. We found that for every 1 month increase in the child's age (proxy for postpartum duration), the likelihood of SPPWR increased by 9% (AOR = 1.09, CI = 1.04-1.15). Mothers were more likely to have SPPWR when they exceeded GWG guidelines (AOR = 3.43, CI = 2.46-4.79). Compared to mothers with normal pre-pregnancy BMIs, mothers with overweight (AOR = .64, CI = .44-.94) and obese (AOR = .39, CI = .26-.58) pre-pregnancy BMIs were less likely to experience SPPWR.

Conclusion: Postpartum duration and maternal anthropometric characteristics were associated with SPPWR during the first postpartum year. Extending WIC eligibility for postpartum mothers to 2 years through the Wise Investment in Children Act may give WIC providers the opportunity to work closely with Southern California WIC mothers to achieve a healthy weight after pregnancy.