Strange-male-induced pregnancy disruption in mice: potentiation by administration of 17 beta-estradiol to castrated males.

Previous evidence suggests that androgen activity is necessary for strange males to disrupt early pregnancy in mice. Inseminated females were housed below castrated males, separated by a wire-mesh grid. Castrated males did not disrupt pregnancy, whereas those given daily injections of 27 or 81 micrograms of 17 beta-estradiol did so. In conjunction with previous evidence, these data suggest a similarity between the hormones involved in the capacity of males to disrupt pregnancy and the hormones directly implicated in the females' vulnerability to pregnancy disruption.