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

Metabolism and motility of human spermatozoa were studied in the presence of steroid hormones and synthetic progestagens. Progesterone and norethynodrel markedly depressed the respiration (p < .001) glycolytic metabolism (p < .001) and the motility of washed spermatozoa. Lynestrenol inhibited motility but did not affect the respiration or glycolysis of the spermatozoa. Estradiol did not alter spermatozoa metabolism consistently and did not affect motility. Progesterone and norethynodrel appear to act on the plasma membrane of spermatozoa to increase its permeability and therefore to facilitate the loss of essential cofactors required for the glycolytic and oxidative processes.