[Effect of intrafollicular interleukin-6 levels on the secretion of estradiol and progesterone in patients treated with in vitro fertilization and embryo transfer].

The objective was to evaluate the relationship between follicular fluid levels of Interleukin-6 (IL-6) and the seric concentrations of estradiol and progesterone during controlled ovarian hyper-stimulation. The levels of IL-6 were measured in follicular fluid of 15 patients undergone to in vitro fertilization and embryo transfer and correlated with the values of seric estradiol and progesterone. There were a negative correlation between follicular levels of IL-6 and either estradiol and progesterone. Four patients achieved pregnancy following embryo transfer (pregnancy rate 26.6%), one of them aborted. As conclusion, the increased levels of IL-6 may be a reaction to controlled ovarian hyper-stimulation and probably a protective response. According to the reduction of estradiol, there may be a subtle reduction in aromatase action by effect of IL-6 and other cytokines.