Modulatory effects of vitamin D on peripheral cellular immunity in patients with recurrent miscarriage

Problem We aimed to investigate the modulatory effects of vitamin D on peripheral blood cellular immune response in patients with recurrent miscarriage ( RM ). Method of study The effect of vitamin D on the number of peripheral blood cells, T helper 1 (Th1) cytokines, and NK cytotoxicity was measured in 99 women with RM . Results The percentage of CD 19 + B cells and NK cytotoxicity at an effector‐to‐target cell (E:T) ratio of 50:1, 25:1, and 12.5:1 were significantly higher in the vitamin D insufficiency group ( VDI ) than in the vitamin D normal group ( VDN ) ( P <.05 each). The proportion of TNF ‐α‐expressing Th cells was significantly higher in the vitamin D deficiency group ( VDD ) than in VDN ( P <.05). However, there were no significant differences between VDI and VDD . This dysregulation was significantly reduced with 1,25( OH ) 2 D supplementation. Conclusion The data suggest that the abnormalities of cellular immune response were observed in RM patients with a low vitamin D level, which could be regulated to some extent with 1,25( OH ) 2 D supplementation.