Effects of a luteinizing hormone-releasing hormone agonist on luteal function in women.

The potent stimulatory luteinizing hormone-releasing hormone (LRH) analogue D-Ser(TBU)6-EA10-LRH was administered once daily during the luteal phase of the human menstrual cycle. The treatment was instituted in the early or mid-luteal phase of the cycle. Early luteal phase institution of intranasal treatment with 600 micrograms of the LRH agonist once daily reduced the basal progesterone levels during the luteal phase in 4 women but did not cause premature onset of menstruation. Mid-luteal phase institution of subcutaneous treatment with 10 micrograms of the LRH agonist once daily did not affect the progesterone levels or reduce the length of the luteal phase in 5 women. Thus, daily postovulatory administration of the LRH agonist D-Ser(TBU)6-EA10-LRH did not cause luteolysis in normally cycling women.