Breast Milk Output and Factors Influencing Sustained Feeding with Mother’s Own Milk in Very Preterm Births: A Prospective Observational Study

Abstract

In very low birth weight infants, mother’s own milk (MOM) feeding is an essential part of the bundle of best practices to reduce potentially preventable neonatal morbidities and associated costs. Mothers of preterm infants can have an altered sequence of lactogenesis because of their preterm delivery and mother–infant separation. Healthy mothers with term infants typically experience coming to volume (CTV), that is, MOM volume of ≥ 500 ml/day, by the end of the second week of postpartum. There is paucity of data regarding MOM output in preterm mothers. To assess MOM output and factors influencing MOM volume among mothers delivering <32 weeks during the first two weeks after birth. To determine the proportion of mothers attaining CTV and whether the first two weeks’ MOM volume predicts MOM feeding at discharge and 40 weeks corrected gestational age (CGA). In this prospective observational study conducted at a tertiary care NICU over a period of 18 months, the milk output of the preterm mothers was quantified, and the proportion of infants fed with MOM at discharge and 40 weeks of corrected age was assessed. The median milk output per day at the end of the first and second weeks was 180 IQR (100, 290) ml and 300 IQR (178, 420) ml, respectively. Earlier initiation of kangaroo mother care, higher birth weight of the infant, increase in the frequency of daytime milk expression and non-nutritive suckling (NNS) contributed to increased MOM output per day. The proportion of mothers who came to volume (milk output of ≥500 ml/day) by day 14 was 26 (19%). The proportion of babies on predominant MOM feeding at discharge and at 40 weeks’ follow-up was 96 (72%) and 75 (61.5%) infants, respectively. Mothers who came to volume were more likely to feed MOM at 40 weeks [odds ratio (OR) 5.2 (1.2–23.0)]. Higher birth weight, more frequency of daytime milk expression, earlier initiation of KMC and NNS and longer duration of KMC are factors improving the MOM output. Mothers who came to volume by the first two weeks after birth sustained feeding with MOM till 40 weeks CGA.