Hormonal regulation of serum and endometrial IL-1 alpha, IL-1 beta and IL-1ra: IL-1 endometrial microenvironment of the human embryo at the apposition phase under physiological and supraphysiological steroid level conditions.

We have investigated serum and intracavitary levels of IL-1 alpha, IL-1 beta and IL-1ra from agonadal women undergoing mock cycles (n = 20) of oocyte donation as a clinical model of controlled hormonal stimulation. Further, we compared the intracavitary IL-1 alpha, IL-1 beta and IL-1ra levels in the microenvironment of the human embryo at the apposition phase, day 5 after progesterone (P) administration using two different clinical models: oocyte donation (n = 20) which provides physiological steroid levels and a higher implantation rate per embryo, and in vitro fertilization (n = 6) with supraphysiological hormonal levels and a lower implantation rate.