Effects of Ovarian Gonadotropin Stimulation under Conditions of Chronic Psychosocial Stress on the Quality of Murine Oocytes

Chronic psychosocial stress can negatively affect the femalereproductive system. Meanwhile, the effect of ovarian stimulationwith gonadotropins during stress on the quality of oocytes remainspoorly studied. This work was aimed to investigate the effects ofchronic psychosocial stress on the quality of murine cumulus-oocytecomplexes under the natural estrus cycle, as well as during theovarian stimulation with exogenous gonadotropins, which is an importantpart of modern assisted reproductive technologies. Here we demonstratethat psychosocial stress does not affect the number of ovulating oocytesbut deteriorates their quality, i.e. reduces the percentage of matureoocytes. In addition, stressed mice exhibited an enhanced accumulationof reactive oxygen species (ROS) in oocytes, accompanied by an increasedapoptosis level in cumulus cells. Hormonal stimulation of the ovarieswith gonadotropins alleviates the negative changes associated withpsychosocial stress, normalizing ROS overproduction in oocytes andreducing apoptosis levels in cumulus cells.