Longitudinal study of human milk creamatocrit and weight gain in exclusively breastfed infants.

OBJECTIVE To determine the creamatocrit values of breastmilk at different lactational periods during the first 6 months after delivery and its relation to infant growth. DESIGN Prospective follow-up study. SETTING Maternity and well baby clinics of a metropolitan teaching, a rural teaching and a suburban municipal hospital. SUBJECTS 1322 exclusively breastfed infants and their mothers. There were 160 preterm, 281 term low birth weight (LBW) and 881 term appropriate for date (AFD) babies. METHODS Creamatocrit of breastmilk and infant's body weight were recorded at 4,8,12,16,20 and 24 weeks after birth. RESULTS Creamatocrit values of breastmilk in all mothers increased upto 16 post partum weeks and then declined. There were no significant differences in creamatocrit values of breastmilk of mothers of preterm, term LBW and term non-LBW infants. Preterm and term LBW infants showed a catch up in body weight with the term AFD group by 20 weeks post-partum. CONCLUSIONS The breastmilk creamatocrit progressively rises upto the fourth month of lactation but is not influenced by gestation or intra uterine growth retardation. There is no relationship between breastmilk creamatocrit and infant growth. Exclusive breast feeding adequately supports growth of LBW infants in comparison to their normal peers during the first 6 months of life.