Background. Human milk contains considerable number of growth factors, including epidermal growth factor (EGF) and insulin-like growth factor-1 (IGF-1). There are no data comparing the EGF and IGF-1 levels in the serum and milk of breast-feeding women. Therefore, the aim of our study was to assess a possible relationship between the concentrations of these growth factors. Material and methods. Thirty-nine women in child-birth were included in the study.
All women provided blood and milk samples during the first six hours after delivery. EGF (by immunoenzymatic method) and IGF-1 (by radioimmunossay method) concentrations were measured in both media.
Results. EGF breast milk concentrations ranged from 3.18 to 4.51 ng/ml and on average were significantly higher (p < 0.0001) than those found in the women’s serum (from 0.02 to 0.13 ng/ml). The opposite distribution was found for IGF-1 levels. Its milk concentrations ranged from 8.8 to 61.9 ng/ml and on average were significantly lower (p < 0.0001) than the serum concentrations (from 192.6 to 595.3 ng/ml). No correlation was found between the serum and milk concentrations of both growth factors.
Conclusion. EGF seems to be synthesized locally in mammary glands, whereas IGF-1 probably permeates into the milk from the vascular bed.