Progesterone, the hormone "pro gestationem," plays a pivotal role in mammalian reproduction during almost all phases of the menstrual cyc1e and all stages of pregnancy. It is involved in the control of ovula tion, prepares the endometrium for implantation, and, in later stages of pregnancy, is responsible for its maintenance by suppressing uterine contractility. The sudden withdrawal of progesterone action at the end of the nonfertile cycle leads to the constriction of spiral arteries and, in . turn, to menstruation in human beings and non human primates. The decrease in serum progesterone...
Progesterone, the hormone "pro gestationem," plays a pivotal role in mammalian reproduction during almost all phases of the menstrual cyc1e and all st...