Teratological experiments with ergotamine in mice, rats, and rabbits

Pregnant mice, rats, and rabbits were treated orally with ergotamine during midgestation. In doses that affected maternal weight gain during treatment, ergotamine produced an increase in prenatal mortality in rats and evidence of fetal retardation in all three species. The results are discussed in connection with the vasoconstrictive action of ergotamine. A uterotonic effect may also be involved in the mechanism of action. No specific teratogenic activity was detected in any of the three species.