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

BACKGROUND: Several stressful environmental factors are associated with short-term breast-feeding. A high concentration of sodium in colostrum has predicted early failure. AIM OF THE STUDY: We studied the association of growth factors in colostrum and the length of breast-feeding (BF). METHODS: We measured concentrations of TGF-β1 and -β2; 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). RESULTS: 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-β1 was 1.9 times as high in the samples from short BF mothers as in those with long BF; sinificant difference remained in comparisons of samples taken equally long postpartum. Samples from the short BF group showed higher levels for sodium, TGF-β2 and total protein, whereas concentrations of epidermal growth factor were similar between groups. CONCLUSIONS: We thus infer that concentrations of factors in breast milk with an effect on the development and involution of the mammary gland, like TGF-β1 in milk, may be one of many biological factors having an impact on the successful initiation of breast-feeding.