Background: The World Health Organization (WHO) recommends exclusive breast-feeding during the first 4 to 6 months of life, but limited information is available regarding the growth performance of infants fed according to the recommendation. The present study used data from the Euro-Growth study to determine the growth of breast-fed European infants who did or did not receive solids from an early age, in comparison with growth of infants who were fed by other modes.
Methods: There were 319 infants who were exclusively breast-fed according to the WHO recommendations for at least 4 to 5 months, and 185 infants who were breast fed but received solids (but no formula) from an early age. There were 1,509 infants who were fed in a variety of ways, which included breast-feeding during the early months of life in the majority (65%) of infants. Anthropometric data were available from birth to 36 months of age. Growth of the two groups of breast-fed infants was assessed by comparing z-scores of length, weight, and body mass index with those of the group fed by other means. Furthermore, multiple regression analysis was used to assess the influence on increment in length and weight of the duration of breast-feeding and the age at which solids were introduced. Euro-Growth references for breast-fed boys and girls were developed and compared with the National Center for Health Statistics (NCHS)-WHO and Euro-Growth references.
Results: The pattern of growth of children who were fed according to the WHO recommendations showed higher weight during the first 2 to 3 months of life and lower weight and length from 6 to 12 months. Between 12 and 36 months of age, differences between groups were small and clinically nonrelevant. Duration of breast-feeding was negatively correlated with increment in length and weight until 12 and 24 months but not until 36 months of age. The influence of duration of breast-feeding was much weaker than that of mid-parental height. The mean and standard deviation z-scores of the Euro-Growth references for weight of breast-fed infants deviate substantially from the NCHS-WHO references during the first 6 months of life in particular. The mean and standard deviation z-scores for length and weight of breast-fed children were close to the Euro-Growth references.
Conclusion: The Euro-Growth references may be used to monitor length, weight, body mass index, and body circumferences of children who are fed according to WHO recommendations. The additional references, which were developed for breast-fed boys and girls, will be useful in view of the commitment of WHO to the collection of data for the development of a new international growth reference.