This study is designed to evaluate blood Th1 and Th2 immunoregulatory cytokine production and hormonal levels associated with the third trimester of pregnancy and the postpartum state. Cytokine and hormone levels will be assessed in blood specimens obtained from healthy pregnant and postpartum females and compared to levels from premenopausal non-pregnant and non-postpartum females. Blood samples obtained at 30-36 weeks of gestation and 2-6 weeks postpartum will be the primary study points. Samples will also be obtained from pregnant, postpartum, and non-pregnant, non-postpartum, premenopausal female patients with rheumatoid arthritis. Additional data will be generated from samples from normal males, which will be compared with data from females.

We expect to find that pregnancy is associated with enhanced Th2 cytokine expression and that the postpartum state is associated with enhanced Th1 cytokine expression. We expect to see differences in cytokine expression between males and females as well. We seek to gather data supporting the view that distinct hormonal environments regulate these contrasting immunological states.