Colostrum TGF-β-1 associates with the duration of breast-feeding

Abstract

Several stressful environmental factors are associated with short-term breast-feeding. A high concentration of sodium in colostrum has predicted early failure. We studied the association of growth factors in colostrum and the length of breast-feeding (BF). We measured concentrations of TGF-beta1 and -beta2; epidermal growth factor, total protein, and sodium and compared their concentrations in colostral samples from mothers who either breast-fed their infants exclusively less than 0.5 months (n = 109) or longer than 3.5 months (n = 119). In the short BF group more mothers smoked and were primiparous more frequently and had less often a university education. They also provided the colostral samples significantly later than did those with long BF. Geometric mean concentration for TGF-beta1 was 1.9 times as high in the samples from short BF mothers as in those with long BF; significant difference remained in comparisons of samples taken equally long postpartum. Samples from the short BF group showed higher levels for sodium, TGF-beta2 and total protein, whereas concentrations of epidermal growth factor were similar between groups. We thus infer that concentrations of factors in breast milk with an effect on the development and involution of the mammary gland, like TGF-beta1 in milk, may be one of many biological factors having an impact on the successful initiation of breast-feeding.