Longitudinal Association of Maternity Care Practices with Exclusive Breastfeeding in U.S. Hospitals, 2018–2022

<b>Background/Objectives</b>: Breastfeeding has health benefits for infants and mothers, and hospitals play an important role in supporting breastfeeding. This analysis examines the longitudinal association of hospital maternity care practices and policies with in-hospital exclusive breastfeeding rates from 2018 to 2022. <b>Methods</b>: U.S. hospitals completing ≥2 surveys during 2018, 2020, and 2022 cycles of CDC's Maternity Practices in Infant Nutrition and Care (mPINC) survey comprised a nested longitudinal cohort (n = 2109). Hospitals were given a modified mPINC score (0 to 100 points) based on self-reported adherence to maternity care practices and policies supportive of breastfeeding, including skin-to-skin contact, monitoring following birth, rooming-in, feeding counseling and education, and institutional policies. Hospitals reported their exclusive breastfeeding rates for healthy infants for the duration of hospitalization. A path analysis quantified the total effects of modified mPINC scores on in-hospital exclusive breastfeeding rates in subsequent survey cycles, controlling for annual births. <b>Results</b>: Among hospitals with the highest modified mPINC scores of 100 points, the mean in-hospital exclusive breastfeeding rates were 62.0% in 2018 (n = 129), 62.2% in 2020 (n = 132), and 61.7% in 2022 (n = 138). Hospitals with the lowest scores of <60 points had exclusive breastfeeding rates of 40.6% (n = 247), 41.9% (n = 173), and 37.8% (n = 127), respectively. Hospitals that increased their modified mPINC score by 10 points from 2018 to 2022, regardless of their score in 2018, had a 2.0 p.p. increase in their exclusive breastfeeding rates. In an adjusted path analysis, each 10-point higher modified mPINC score in 2018 was associated with a 4.4 (95% CI, 4.0-4.9) percentage point higher exclusive breastfeeding rate in 2022-through increasing the likelihood of higher in-hospital exclusive breastfeeding rates in 2018 and 2020 and higher modified mPINC scores in 2020 and 2022. <b>Conclusions</b>: Improving and sustaining maternity care practices and policies supportive of breastfeeding are associated with higher in-hospital exclusive breastfeeding over time.