Growth and gastrointestinal tolerance of healthy formula-fed infants: a multicentre, prospective observational study

BACKGROUND: Infant formula with human milk oligosaccharides (HMOs) and increased β-palmitate mimics breast milk nutritional composition and clinical benefits. We aimed to assess formula-fed infant growth, gastrointestinal tolerance, infections, and parental satisfaction with a partly fermented infant formula with an improved lipid profile (enriched with β-palmitate and docosahexaenoic/arachidonic acid) and short and long-chain oligosaccharides (scGOS/lcFOS [9:1]) and HMOs. METHODS: A prospective descriptive observational study in healthy infants with formula feeding or breastfeeding (reference population) was conducted in six Spanish primary care centres following routine clinical practice. In the first, second and fourth month of life visits sociodemographic, clinical, and anthropometric variables (weight, length, head circumference), stool consistency (Brussels Infant and Toddler Stool Scale [BITSS]), gastrointestinal symptoms, infections incidence and associated healthcare resource utilisation, and caregivers' satisfaction with formula were collected. A descriptive statistical analysis was performed (STATA-v.14). Growth was estimated as the mean (standard deviation) increase in the anthropometric variables and z-scores. RESULTS: A total of 61 formula-fed and 65 breastfed infants were included in the study (50.8% male). The average increase in weight, length and head circumference in the formula feeding and in the breastfeeding groups from the first to the fourth month of life was 2,566 (496) g, 9.7 (1.7) cm and 4.4 (1.0) cm, and 2,571 (702) g, 9.8 (1.8) cm and 4.4 (1.1) cm, respectively. The weight z-score was -0.1 (0.7) for formula-fed and 0.1 (1.1) for breastfed infants. In all visits, more than 88% of infants had loose/watery stools and most infants suffered gastrointestinal symptoms with low/medium frequency. In the fourth month of life visit, 16 (26.2%) formula-fed and 16 (24.6%) breastfed infants had infections, mainly respiratory, with 16% of formula-fed and 12% of breastfed infants requiring treatment. Most formula-feeding caregivers had a good/very good opinion of formula (85.2%). 75.4% infants drank the whole feeding bottle. CONCLUSIONS: The growth, gastrointestinal tolerance, and incidence of infections of healthy formula-fed infants during the first four months of life were appropriate and in line with WHO standards. Formula feeding caregivers were satisfied with this partly fermented infant formula with an improved lipid profile and oligosaccharides.