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Neonatal weight loss at a US Baby-Friendly Hospital
Xena Grossman1, Jana H Chaudhuri, Lori Feldman-Winter
1Boston University School of Medicine, Division of General Pediatrics, Boston Medical Center, Boston, MA 02118, USA.
Insights
Newborn weight loss in the first week is typically moderate, averaging 4.9%. Breastfeeding is associated with slightly higher weight loss compared to formula feeding, but still within normal ranges.
Area of Science:
- Neonatal Health
- Pediatric Nutrition
- Maternal-Child Health
Background:
- Limited data exist on normal newborn weight loss patterns in the United States.
- There is no established standard for typical newborn weight loss during the first week of life.
- Previous studies have not consistently tracked daily infant weight for the initial seven days.
Purpose of the Study:
- To investigate normal newborn weight loss patterns.
- To establish benchmarks for infant weight loss in the first week of life.
- To analyze factors influencing newborn weight loss, including feeding type.
Main Methods:
- Prospective cohort study involving 121 term newborns in a US Baby-Friendly hospital.
- Daily infant weighing for the first week of life (in-hospital and at home post-discharge).
- Recording of all infant feeds and abstraction of birth-related factors.
Main Results:
- Mean newborn weight loss was 4.9%, with a range of 0.0% to 9.9%.
- 19.8% of infants lost more than 7% of their birth weight; none lost over 10%.
- Maximum weight loss was significantly associated with feeding type: exclusively/mainly breastfed (5.5%), mainly formula-fed (2.7%), exclusively formula-fed (1.2%).
Conclusions:
- Clinical practices in Baby-Friendly hospitals support moderate weight loss in breastfed infants.
- Breastfeeding is associated with slightly higher, yet normal, weight loss compared to formula feeding.
- Delivery type and intrapartum fluids did not significantly impact newborn weight loss.
Abstract:
Few if any studies have examined weight loss among term newborns by weighing infants daily for the first week of life. Perhaps because so few data exist, there is no standard in the United States for normal newborn weight loss. Our objective was to investigate normal newborn weight loss among infants born in a US Baby-Friendly hospital, by weighing infants daily for the first week of life. Using a prospective cohort design, infants born at an urban Boston, MA, hospital were enrolled within 72 hours of delivery and weighed daily for the first week of life. In hospital, infant weight was obtained from the medical record; post discharge, a research assistant visited the home daily and weighed the baby. All feeds in week 1 of life were recorded. Birth-related factors potentially affecting weight loss were abstracted from the medical record. Complete data were collected on 121 infants. Mean weight loss was 4.9% (range=0.0% to 9.9%); 19.8% (24 of 121) of infants lost >7% of their birth weight; no infant lost >10%. Maximum percent weight loss was significantly associated with feeding type: exclusively and mainly breastfed infants lost 5.5%, mainly formula-fed infants lost 2.7% and exclusively formula-fed infants lost 1.2% (P<0.001). Type of delivery and fluids received during labor were not associated with weight loss. Clinical practices at a Baby-Friendly hospital, which support and optimize breastfeeding, appear to be associated with only moderate weight loss in exclusively and mainly breastfed infants.
