A longitudinal study of cell-mediated immunity in human pregnancy.

Studies of cell-mediated immunity, comprising delayed hypersensitivity skin testing with four antigens, PHA and antigen-induced lymphocyte transformation and detection of the lymphokine, monocyte chemotactic factor, were undertaken in 14 women during pregnancy and in the post-natal period. Skin test reaction sizes to SKSD, PPD, Candida albicans extract and tetanus toxoid were not significantly different during pregnancy. In vitro lymphocyte transformation induced by PHA, SKSD and Candida albicans was enhanced during pregnancy. Monocyte chemotactic factor production was not significantly different during pregnancy. These in vitro tests were performed in the absence of autologous sera. These studies indicate that cell-mediated immune responses are normal during human pregnancy.