Prostaglandin E2 and the luteal phase of the menstrual cycle: effects on blood progesterone, estradiol, cortisol, and growth hormone levels

An iv infusion of prostaglandin E2 (PGE2) was given for 8 hr on 2-3 consecutive days to 7 normally cycling women during various periods of the luteal phase, and to 1 woman whose luteal phase was prolonged by hCG administration. Three women were infused with saline solution only. During PGE2 infusion 2 hourly blood samples showed some variations in progesterone and estradiol levels regardless of the period of the luteal phase; no clear-cut depression was noted. These changes were similar to the spontaneous variations seen in controls. PGE2 did not induce intermenstrual bleeding or premature menstruation, although uterine contractility was markedly increased. In 1 subject PGE2 was given during the early postovulatory period without interfering with implantation and subsequent normal pregnancy. An increase of cortisol and GH blood levels was also observed during PGE2 infusion. We conclude that PGE2 in the doses used is not luteolytic in humans.