ulipristal and Ovarian-Cysts

Previous studies in women have shown that the antiprogestin mifepristone delays or inhibits folliculogenesis. The purpose of this study was to explore whether a new analogue, CDB-2914, has similar effects on folliculogenesis, ovulation, or on subsequent luteal phase endometrial maturation. Forty-four normally cycling, healthy women recorded urine LH and vaginal bleeding during pre-treatment, treatment, and post-treatment cycles. At a lead follicle diameter of 14-16 mm, a single oral dose (10, 50, 100 mg) of CDB-2914 or placebo was given, and daily ultrasound, oestradiol and progesterone were obtained until follicular collapse; an endometrial biopsy was obtained 5-7 days later. Single doses of CDB-2914 were well tolerated. Mid-follicular CDB-2914 suppressed lead follicle growth, causing a dose-dependent delay in folliculogenesis and suppression of plasma oestradiol. At higher doses, a new lead follicle was often recruited. Although luteinized unruptured follicles were observed at the 100 mg dose, all women had follicular collapse. There was a significant delay in endometrial maturation after CDB-2914 at all doses. The treatment cycle was lengthened by 1-2 weeks in 30% at 100, 27% at 50 and 9% at 10 mg. CDB-2914 altered ovarian and endometrial physiology without major effects on menstrual cyclicity and may have therapeutic utility.

Topics: Adolescent; Adult; Biopsy; Cell Differentiation; Contraceptives, Postcoital, Synthetic; Dose-Response Relationship, Drug; Endometrium; Estradiol; Female; Humans; Luteinizing Hormone; Menstrual Cycle; Norpregnadienes; Ovarian Cysts; Ovarian Follicle; Ovulation