- Data from 463 premature infants was gathered.1 This is a prospective cohort trial. Infants were placed into 4 different feeding groups, based on the percentage of breast milk vs formula consumed prior to discharge from the hospital after birth. Growth parameters, visual acuity testing, and development assessment were followed at specific intervals in the first 15 months of life. Strengths of the study include information gathered from different countries (US, UK, Chile), length of study, objective data (growth parameters) followed. Weaknesses include: initial aim of study to evaluate effect on development of premature formulas containing differing amounts of essential fatty acids (AA, DHA), 19% of infants lost to follow-up during 15 month study, use of subjective data (visual acuity, developmental assessment), no randomization or blinding to researchers.
- Infants fed breast milk, may initially grow (weight, head circumference, height) at a slower rate than those fed formula. At term chronological age (approximately 7-8 weeks of life), premature infants fed predominantly breast milk weight 18.5% less than those fed predominantly formula.
- Infants fed breast milk, “catch up” to those fed formula by 12 months of age. The difference in weight between premature infants fed predominantly breast milk and those fed formula was only 4% at 12 months of age. By 4 months of age, both groups had similar head circumference measurements. By 9 months of age, both groups had similar length measurements.
- Per Teller visual card testing, there may be increased visual acuity in premature infants who are fed any appreciable amount of breast milk. However, this difference disappears after 6 months of age.
- Development (as measured by Bayley Motor and Mental Index) is the same for premature infants fed formula or breast milk. However scores are still lower in any premature infant as compared to term infants.
- Decreased morbidity among predominantly breast milk fed infants: fewer adverse outcomes as measured by NEC complication, and rehospitalization.
- Preterm infant formulas fortified with Arachidonic and Docosahexaenoic acids may not confer the added benefits (improved brain and visual development) once previously thought.3