Risk factors for suboptimal infant breastfeeding behavior, delayed onset of lactation, and excess neonatal weight loss.

OBJECTIVE: Some mothers have difficulty initiating lactation even when highly motivated to breastfeed. The purpose of this study was to determine the incidence of and risk factors for suboptimal infant breastfeeding behavior (SIBB), delayed onset of lactation, and excess neonatal weight loss among mother-infant pairs in a population with high educational levels and motivation to breastfeed.
METHODS: All mothers residing in Davis, California, who gave birth to a healthy, single, term infant at 1 of 5 area hospitals during the 10-month recruitment period in 1999 were invited to participate if they were willing to attempt to breastfeed exclusively for at least 1 month. Lactation guidance was provided and data were collected in the hospital (day 0) and on days 3, 5, 7, and 14. Infant breastfeeding behavior was evaluated by trained lactation consultants using the Infant Breastfeeding Assessment Tool. Onset of lactation was defined based on maternal report of changes in breast fullness. Infant weight loss was considered excessive if it was >or=10% of birth weight by day 3.
RESULTS: Of the 328 eligible mothers, 280 (85%) participated in the study. The prevalence of SIBB was 49% on day 0, 22% on day 3, and 14% on day 7. SIBB was significantly associated with primiparity (days 0 and 3), cesarean section (in multiparas, day 0), flat or inverted nipples, infant status at birth (days 0 and 3), use of nonbreast milk fluids in the first 48 hours (days 3 and 7), pacifier use (day 3), stage II labor >1 hour (day 7), maternal body mass index >27 kg/m(2) (day 7) and birth weight <3600 g (day 7). Delayed onset of lactation (>72 hours) occurred in 22% of women and was associated with primiparity, cesarean section, stage II labor >1 hour, maternal body mass index >27 kg/m(2), flat or inverted nipples, and birth weight >3600 g (in primiparas). Excess weight loss occurred in 12% of infants and was associated with primiparity, long duration of labor, use of labor medications (in multiparas), and infant status at birth. The risk of excess infant weight loss was 7.1 times greater if the mother had delayed onset of lactation, and 2.6 times greater if the infant had SIBB on day 0.
CONCLUSIONS: Early lactation success is strongly influenced by parity, but may also be affected by potentially modifiable factors such as delivery mode, duration of labor, labor medications, use of nonbreast milk fluids and/or pacifiers, and maternal overweight. All breastfeeding mother-infant pairs should be evaluated at 72 to 96 hours' postpartum.