The metabolism and motility of human spermatozoa in the presence of steroid hormones and synthetic progestagens.

The metabolism and motility of human ejaculated spermatozoa incubated in vitro with steroids were studied. Progesterone and norethynodrel depressed the respiration, glycolytic metabolism and the motility of washed spermatozoa. Lynoestrenol did not affect the respiration or glycolysis of the spermatozoa, but did inhibit motility. Oestradiol did not cause any consistent alteration of the sperm metabolism, and did not affect the motility. Progesterone and norethynodrel appeared to act on the plasma membrane of human spermatozoa to increase its permeability and hence to facilitate the loss of essential cofactors required for the glycolytic and oxidative processes.