Abstract: It has been found that the active principles of zoapatle are (-)-kaura-9(11),16-dien-19-oic acid, kaurenoic acid and monoginoic acid and that these acids at prescribed dosages may be used for altering the behavior of the reproductive system of a female mammal; such alterations may include inducing menses in adult female primates, synchronizing the estrous cycle in a group of mammals and preventing birth in female mammals, thus acting as a contraceptive.

Abstract: A pharmaceutical composition obtainable by extraction from Montanoa tomentosa is useful for controlling fertility in female mammals. By internal administration of an effective luteolytic amount of the herbal product, blood levels of progesterone can be controlled and in the case of female humans and other primates such as monkeys, menses may be induced. Antiimplantation or pregnancy termination methods may be utilized for humans and lower animals. Biologically synchronized and controlled fertility techniques permit members of a mammalian group to become fertile in a close time period for reducing the time span in which newborn animals, such as sheep, are delivered.