Socio-demographic Correlates of Pre-pregnancy Body Mass Index Among Low-income Women in Hawaii WIC Participating in a Randomised Trial

Abstract

\n Background: A healthy pre-pregnancy BMI fosters positive outcomes for both mother and infant both during and after pregnancy. To design interventions to promote a healthy pre-pregnancy BMI in low-income women, it is important to understand correlates. The purpose of this study was to identify the socio-demographic correlates of pre-pregnancy body mass index (BMI) among low-income women.Methods: Participants were low-income pregnant women (n=83) in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in Hawai‘i enrolled in a four-month text message-based nutrition intervention program. Participants reported pre-pregnancy weight and height and completed a demographics questionnaire on age, race/ethnicity, education, employment status and number of children. Descriptive statistics (mean, standard deviation for continuous variables, and frequencies and proportions for categorical variables) were used to summarize the sample. Simply linear regression analyses were performed to examine if independent variables were associated with BMI before pregnancy. Results: Among the 83 women, 33 (39.8%) were 18-24 years old, 22 (26.5%) were between 25 and 29, 19 (22.9%) were 30-34 and 9 (10.8%) were 35-41. A total of 18 (21.7%) were Asian. Age and race/ethnicity were marginally associated with BMI before pregnancy. The age group 30-34 had the highest BMI before pregnancy (p=0.06) and Asian had lower BMI before pregnancy than the other races/ethnicities (p=0.01). Conclusions: Being classified as Asian was associated with lower BMI before pregnancy, while those who were 30-34 years old had the highest pre-pregnancy BMI compared to other age groups. These socio-demographic factors should be taken into account when designing interventions to promote healthy weight in women of childbearing age. Trial registration: The trial is registered on clinicaltrials.gov (NCT04330976). Date of registration April 2, 2020 (restrospectively registered). URL: https://clinicaltrials.gov/ct2/show/NCT04330976