Date of Award

January 2024

Document Type


Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Yasmmyn D. Salinas

Second Advisor

Nicola Hawley


Background: The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) has been an impactful federal public assistance program that has provided nutrition education and support to millions of low income women and children around the country. Despite its positive impact on perinatal and birth outcomes, the precise mechanisms between WIC and these outcomes remain unclear. Past studies have looked at the relationship between WIC and gestational weight gain (GWG), a potential mediator of the effect of WIC on birth outcomes, but they have mainly focused on city or state level data or Medicaid enrollees. This study aims to estimate the effect of WIC on excessive and inadequate GWG in a nationally representative sample of WIC participants and also identify potential effect modifiers in the relationship between WIC and GWG.

Methods: Data from this study came from the National Center for Health Statistics birth data files between the years 2020-2022. The relationship between WIC participation and GWG was analyzed using polychotomous logistic regression models.

Results: After covariate adjustment, WIC participants had 0.99 times the odds of gaining inadequate GWG (Odds ratio:0.99, 95% CI:0.98-1.00) and 1.04 times the odds of gaining excessive GWG (Odds ratio: 1.04, 95% CI: 1.03-1.05). The effect modifiers of the relationship between WIC and GWG were race, age, education attainment, marital status, nativity status, insurance type, pre-pregnancy BMI, gestational diabetes status, gestational hypertension status, hypertension eclampsia status, pre-pregnancy diabetes status, pre-pregnancy hypertension status, smoking during pregnancy status, and prenatal care utilization adequacy. After conducting subgroup analyses, WIC had protective effects against inadequate GWG in Hispanics, Medicaid recipients, unmarried participants, participants with no high school degree, mothers who were underweight, and mothers who had inadequate prenatal care utilization. With respect to excessive GWG, WIC largely had a harmful effect across all subgroups.

Conclusions: This study highlights the slightly protective effect against inadequate GWG and the harmful effects of WIC on GWG on a nationally representative sample of WIC participants. This elevated risk of excessive GWG underscores the importance of improving nutritional counseling strategies within the WIC program to promote healthy weight management during pregnancy, especially given the obesogenic environment of the US.


This thesis is restricted to Yale network users only. It will be made publicly available on 05/07/2026