The effect of various steroids on mating behavior, fertility, and fecundity of rats
Peterson, D.L.; Edgren, R.A.
International Journal of Fertility 10(4): 327-332
1965
ISSN/ISBN: 0020-725X PMID: 5842643 Document Number: 472593
Female rats were treated for 35 days with various natural and synthetic sex steroids. On the 6th day of treatment males were introduced, and the females were examined daily for the presence of sperm in the vaginal smear. At the doses employed, testoids and "pure" progestagens had little effect upon mating behavior (as determined by acceptance of males), fertility, or fecundity (litter size). Estrogens and estrogenic "progestagens" (norethynodrel, nore-thisterone acetate) prevented conception during treatment, although multiple matings were frequent. Termination of treatment was followed by a recovery of fertility in virtually all animals within 6 months. No consistent fetal abnormalities were observed in this experiment, although the incidence of fetal death and abnormality appeared to be highest in females that received the estrogens, either alone or in combination with a progestagen.