A comparative study of cells and anti-microbial proteins in colostrum of mothers delivering pre- and full-term babies.

The different anti-infective factors in the colostrum of 25 mothers delivering pre-term (33.04 +/- 2.18 weeks gestation) and 10 mothers full delivering term (39.1 +/- 0.87 weeks gestation) babies were measured. The mothers of both the groups were comparable with respect to age, parity, nutrition, and haemoglobulin levels. Although the mean volume of colostrum (12 hours) was significantly lower in pre-term (32.28 +/- 7.92 ml) than in full term (44 +/- 4.83 ml) colostrum (P less than 0.05), the concentrations of total protein, sIgA, lysozyme, and lactoferrin were significantly higher in preterm than in full-term colostrum. IgG and IgM levels were similar in both the groups of colostrum. In both the groups, s-IgA was the predominant immunoglobulin. Moreover, the absolute counts of total cells, macrophages, lymphocytes, and neutrophils were significantly higher in pre-term compared to full-term colostrum. Macrophage were the predominant cells. Degree of prematurity has been found to have profound influence on the volume, protein concentration, and cell and macrophage counts of colostrum. Thus, more pre-term the newborn was, the mother produced less amount of colostrum. Total protein concentration and absolute cell count were significantly higher in the colostrum samples of mothers delivering between 28 and 32 weeks as compared to those delivering between 33 and 36 weeks. It is concluded that the colostrum of mothers delivering pre-term, though less in amount, is rich in soluble anti-infective agents and cells. The higher concentration of protective factors compensates for the limited capacity of milk intake in the pre-term infant.