The effects of sex hormones on the immune system in pregnancy.

The immune system is affected by sex steroids. Immunoglobulin synthesis, T-cell subsets, and a variety of cytokines are targets for sex steroids. Hormonal variations are found in patients with rheumatic diseases. These variations include the hydroxylation of estrone and the oxidation of testosterone, both of which are altered in rheumatic disease. These changes are magnified in the pregnant state. More estrogen metabolites of the C-16 variety can bind to cells (lymphocytes and erythrocytes) and his reaction is accelerated in pregnancy. The role of the catechol estrogens is discussed. These compounds may be important to some of the vasospastic symptoms seen during pregnancy in patients; moreover, oxidation of testosterone to weak androgens is found in women with systemic lupus erythematosus (SLE). Overall, interesting observations and conclusions will evolve from a better understanding of sex hormone metabolism and its effects on the immune system in pregnancy.