Effects of formula supplementation in breast-fed infants with failure to thrive.

BACKGROUND: The aim of the present study was to assess whether formula supplementation of infants with failure to thrive can improve underweight without jeopardizing breast-feeding. METHODS: In a prospective intervention study 31 term exclusively breast-fed infants were studied, who were admitted to hospital at an age of 28-99 days with failure to thrive (< or =40% expected weight gain for age and/or bodyweight < or =10th percentile for age) without underlying disease. Infant formula was offered ad libitum after each breast-feeding, while continued breast-feeding was supported. RESULTS: Energy intake per day increased from 352 +/- 111 kJ/kg (mean +/- SD) at study start to 587 +/- 115 kJ/kg (P < 0.001, days 1-3 of supplementation) and 501 +/- 99 kJ/kg (days 29-31; P < 0.001 vs study entry). Twenty-five infants continued to be partially (n = 21) or fully (n = 4) breast-fed. Human milk intake decreased from 476 +/- 163 g/day (study days 1-3) to 349 +/- 285 g/day (study days 29-31; P < 0.01). The contribution of breast milk to total milk intake decreased from 100% to 42 +/- 35% (P < 0.001). Supplementation over 31 days led to increased weight (0.98 [0.70], standard deviation scores [SDS]), length (+0.40 [0.41] SDS) and head circumference (+0.59 [0.93] SDS). CONCLUSIONS: One month of formula supplementation successfully improved growth in 72% of infants with failure to thrive on human milk feeding. Breast-feeding was maintained in 81% of infants.