[Chromosomal disorders in the oocytes of rats after stress exposure in the preovulatory period].

Female rats at the stage of proestrus have been subjected to a stress effect--immobilization for an hour. Oocytes were cytogenetically analyzed and embryonal mortality was determined. It is shown that this stress effect at the end of the fist meiotic division of the oocytes increased the rate of aneuploid gametes and the level of embryonal mortality.