The influence of exercise during pregnancy on racial/ethnic health disparities and birth outcomes

Non-Hispanic black (NHB) pregnant women disproportionately experience adverse birth outcomes compared to Non-Hispanic white (NHW) pregnant women. The positive effects of prenatal exercise on maternal and neonatal health may mitigate these disparities. This study evaluated the influence of prenatal exercise on racial/ethnic disparities in gestational age (GA), birthweight (BW), and risks of preterm birth (PTB), cesarean section (CS), and low-birthweight (LBW) neonates.

This study performed a secondary data analysis using data from a 24-week, two-arm exercise intervention trial (ENHANCED by Mom). Women with singleton pregnancies (< 16 weeks), aged 18-40 years, BMI between 18.5-34.99 kg/m², and no preexisting health conditions were eligible. The aerobic exercisers (EX) participated in 150 min of moderate-intensity weekly exercise while non-exercising controls (CON) attended low-intensity stretching/breathing sessions. Data on GA, PTB (< 37 weeks), BW, LBW (< 2.5 kg), and delivery mode were collected. Poisson, median and linear regressions were performed.

Participants with complete data (n = 125) were eligible for analyses (EX: n = 58, CON: n = 67). NHB pregnant women delivered lighter neonates (β = - 0.43 kg, 95% CI: - 0.68, - 0.18, p = 0.001). After adjusting for prenatal exercise, racial/ethnic disparities in BW were reduced (β = - 0.39 kg, 95% CI: - 0.65, - 0.13, p = 0.004). Prenatal exercise reduced borderline significant racial/ethnic disparities in PTB (p = 0.053) and GA (p = 0.07) with no effects found for CS and LBW.

The findings of this study demonstrate that prenatal exercise may attenuate the racial/ethnic disparities observed in neonatal BW, and possibly GA and PTB. Larger, diverse samples and inclusion of maternal biomarkers (e.g., cytokines) are encouraged to further evaluate these relationships.