RECOVERY FROM OESTROGEN-INDUCED STERILITY IN ALBINO MICE

Abstract

1. Male albino mice were rendered sterile by the injection of 2·5–40 μg. of oestradiol benzoate in nut oil B.P. twice weekly. Seven out of eight mice were sterile after 6 weeks of injections of 10 μg. Testicular damage was seen histologically in some males, and a highly significant weight loss occurred in the testes of all groups. These effects rapidly disappeared when injections ceased, and full fertility and normal testicular weight were regained. 2. The control groups of males in these tests, while showing no testicular abnormalities, lost fertility to some extent when injected with either nut oil or physiological saline. This loss was also regained when injections ceased. 3. Female albino mice were rendered sterile by the injection of 0·5–12·5 μg. of oestradiol benzoate in nut oil twice weekly for 4 weeks. Even the lowest dose caused complete sterility during the period of injections and for 2 weeks thereafter. Recovery from all dose levels was apparently complete, although mice receiving 12·5 μg. took from 41 to 125 days to produce a litter when injections were stopped.