Postpartum maternal blood helper T (CD3+CD4+) and cytotoxic T (CD3+CD8+) cells: correlations with iron status, parity, supplement use, and lactation status.

Iron deficiency reduces T cell counts; however, iron sufficiency is difficult to maintain during pregnancy and to reestablish in the early postpartum period. This cross-sectional study examined relations among postpartum maternal iron status, parity, lactation, supplement use, and maternal blood T cell populations. Sixty lactating and 41 nonlactating postpartum (NLPP) women at 1-2 wk and 1, 2, 4, or 8 mo postpartum and 13 nulliparous women were studied. Among multiparous women, multiple linear regression showed that relative percentages and absolute numbers of CD3+CD8+ cells were correlated positively with maternal serum transferrin saturation. In a separate multiple linear regression model, multiparous NLPP women who did not use multivitamin and mineral supplements had lower CD3+CD4+ cell percentages in the first month postpartum than did nulliparous control women. Lactating women who used supplements, however, had reduced CD3+CD4+ percentages 4-8 mo postpartum compared with control women. CD3+CD4+ percentages did not differ among control women, NLPP women who used supplements, or lactating women who did not use them. These results suggest that nutritional factors such as maternal iron status and use of dietary supplements play a role in a mother's postpartum immune status.