Objective: To test a novel protocol of luteal phase administration of clomiphene citrate (CC) for ovulation induction in women with polycystic ovary syndrome (PCOS).
Design: Prospective, randomized, controlled trial.
Setting: University teaching hospital and private practice settings.
Patient(s): The study comprised a total of 212 women (438 cycles) with PCOS.
Intervention(s): Patients in the early CC group received 100 mg of CC daily starting the next day after finishing medroxyprogesterone acetate (MPA) for 5 days (110 patients, 227 cycles), whereas the patients in the late CC group received 100 mg of CC daily for 5 days starting on day 3 of the menses (102 patients, 211 cycles).
Main outcome measure(s): Number of growing and mature follicles, serum E(2) (in picograms per milliliter), serum P (in nanograms per milliliter), endometrial thickness (in millimeters), occurrence of pregnancy and miscarriage.
Result(s): There were more ovulating patients in the early CC group (59.1% vs. 51.9%), without significant differences. The total number of follicles and the number of follicles >or=14 mm and >or=18 mm during stimulation were significantly greater in the early CC group. The endometrial thickness at the time of hCG administration was significantly greater in the early CC group (9.1 +/- 0.23 vs. 8.2 +/- 0.60 mm). Serum E(2) and P were not significantly different between the two groups. Pregnancy occurred in 23/110 cycles in the early CC group (20.9%) and 16/102 cycles (15.7%) in the late CC group; the difference was not statistically significant. The miscarriage rate was similar in the two groups.
Conclusion(s): Early administration of CC in patients with PCOS will lead to more follicular growth and endometrial thickness, which might result in a higher pregnancy rate (PR).