THE NCHS REFERENCE AND THE GROWTH OF BREAST-FED AND BOTTLE-FED INFANTS

The current international growth reference, the National Center for He alth Statistics (NCHS) reference, is widely used to compare the nutrit ional status of populations and to assess the growth of individual chi ldren throughout the world. Recently, concerns were raised regarding t he adequacy of this reference for assessing the growth of breast-fed i nfants. We used the NCHS reference to evaluate infant growth in one of the most developed areas of Brazil. Infants who were exclusively or p redominantly breast-fed for the first 4-6 mo, and partially breastfed thereafter, grew more rapidly than the NCHS reference in weight and le ngth during the first 3 mo, but appeared to falter thereafter. The ave rage growth of all infants, regardless of feeding pattern, was faster than the NCHS reference until similar to 6 mo, after which their growt h became slower than that of the NCHS sample. To substantiate this fin ding, the NCHS growth curves were then compared with growth data of br east-fed infants in developed countries from pooled published studies, formula-fed North American and European infants and predominantly bot tle-fed U.S. infants monitored by the Centers for Disease Control and Prevention (CDC) Pediatric Surveillance System. in all three cases, we ights showed the same pattern as the Brazilian infants-higher than NCH S in the early months but an apparent decline thereafter. The pattern for length gain was similar but less marked. Breastfed infants showed more pronounced declines than those who were predominantly bottle-fed. These findings suggest that the infancy portion of the NCHS reference does not adequately reflect the growth of either breastfed or artific ially fed infants. This probably results from characteristics of the o riginal sample and from inadequate curve-fitting procedures. The devel opment of an improved international growth reference that reflects the normal infant growth pattern is indicated.