Abstract
OBJECTIVE: To assess racial and ethnic disparities in birth weight (BW), time to BW regain, and mean growth velocity during the accelerated weight gain phase. STUDY DESIGN: A retrospective study was conducted using a de-identified dataset from the Pediatrix Medical Group from 2010 to 2020. The dataset categorizes infants into five racial and ethnic groups: Asian, Hispanic, Black, White, and Other, based on maternal report. The study included infants born between 23 and 29 weeks' gestation and excluded infants without weight data. RESULTS: This study included 76,145 infants. Antenatal confounders were balanced using inverse propensity weighting. Black infants had lowest, while Hispanic infants had higher BW z-scores, when compared to White infants. Black infants took the shortest time to regain BW. Hispanic infants had the lowest mean growth velocity. CONCLUSION: Racial and ethnic disparities in postnatal growth of infants born before 30 weeks of gestation manifest differently across growth phases.