Breastfeeding-associated hypernatremia: are we missing the diagnosis?

Pediatrics. 2005 Sep;116(3):e343-7. doi: 10.1542/peds.2004-2647.


Objectives: To assess the incidence and complications of breastfeeding-associated hypernatremic dehydration among hospitalized neonates.

Study design: A retrospective study was conducted at Children's Hospital of Pittsburgh over a 5-year period, to identify otherwise healthy term and near-term (> or =35 weeks of gestation) breastfed neonates (<29 days of age) who were admitted with serum sodium concentrations of > or =150 mEq/L and no explanation for hypernatremia other than inadequate milk intake.

Results: The incidence of breastfeeding-associated hypernatremic dehydration among 3718 consecutive term and near-term hospitalized neonates was 1.9%, occurring for 70 infants. These infants were born primarily to primiparous women (87%) who were discharged within 48 hours after birth (90%). The most common presenting symptom was jaundice (81%). Sixty-three percent of infants underwent sepsis evaluations with lumbar puncture. No infants had bacteremia or meningitis. Infants had hypernatremia of moderate severity (median: 153 mEq/L; range: 150-177 mEq/L), with a mean weight loss of 13.7%. Nonmetabolic complications occurred for 17% of infants, with the most common being apnea and/or bradycardia. There were no deaths.

Conclusion: Hypernatremic dehydration requiring hospitalization is common among breastfed neonates. Increased efforts are required to establish successful breastfeeding.

MeSH terms

  • Apnea / etiology
  • Bradycardia / etiology
  • Breast Feeding / adverse effects*
  • Dehydration / etiology
  • Humans
  • Hypernatremia / diagnosis
  • Hypernatremia / etiology*
  • Infant, Newborn
  • Weight Loss