Effects of Ovarian Stimulation with Gonadotropins in the Conditions of Chronic Psychosocial Stress on the Quality of Murine Oocyte

Chronic psychosocial stress may negatively affect the female reproductive system. Meanwhile, the effect of ovarian stimulation with gonadotropins during stress on the quality of oocytes remains poorly studied. The purpose of this work was to investigate the effects of chronic psychosocial stress on the quality of murine cumulus-oocyte complexes during natural estrus cycle, as well as during ovarian stimulation with exogenous gonadotropins; the latter is an important part of modern assisted reproductive technologies. The results of the study demonstrate that psychosocial stress does not affect the number of ovulating oocytes, but worsens their quality, i. e. reduces the percentage of mature oocytes. In addition, stressed mice exhibited the increased accumulation of reactive oxygen species in oocytes, which is accompanied by the enhanced rate of apoptosis in cumulus cells. Hormonal stimulation of the ovaries with gonadotropins alleviates the negative changes associated with the psychosocial stress, normalizing the level of reactive oxygen species in oocytes and reducing the rate of apoptosis in cumulus cells.