Controlled ovarian hyperstimulation in assisted reproduction: effect on the immune system

Objective: To determine how controlled ovarian hyperstimulation (COH) in assisted reproduction affects the immune system. Design: A prospective, nonrandomized, case-control study. Setting: Academic research setting. Patient(s): Women with regular menstrual cycles undergoing COH in an assisted reproduction program. Intervention(s): Blood samples were collected in the early and late follicular phase, at the time of ovulation, and in the luteal phase during a natural cycle, and at four times during the next cycle, which included COH and IVF. Main Outcome Measure(s): Lymphocyte subpopulations and the differential blood count. Result(s): In the natural cycles, a significant increase in the total numbers of lymphocytes, B cells, natural killer cells, and CD3+HLADR+ cells was observed in the late follicular phase, whereas the T helper/T suppressor cell ratio declined. In the hyperstimulated cycles, increases were seen in the total numbers of leukocytes and neutrophils on the day of hCG administration; the number of lymphocytes, monocytes, and neutrophils was increased on the day of oocyte retrieval, and the total number of leukocytes and neutrophils increased during the luteal phase. Conclusion(s): Controlled ovarian hyperstimulation with hMG and simultaneous administration of a GnRH antagonist did not affect the immune system. (Fertil Steril(R) 1998;70:831-5. (C) 1998 by American Society for Reproductive Medicine.).