RESUMO
AIM: To compare the ovarian response to early versus late clomiphene citrate (CC) in women with polycystic ovary syndrome (PCOS). METHODS: This cross-over randomized controlled clinical trial included 90 infertile amenorrheic women with PCOS. After inducing withdrawal bleeding, patients were randomly divided into two equal groups to receive ovulation induction with CC 100 mg/day for 5 days. Group I started treatment the next day after finishing medroxyprogesterone acetate course for a menstrual cycle, and after a washout period of another menstrual cycle, the treatment was shifted to start on day 2 of withdrawal bleeding. Group II received a reversed protocol: late then early treatment. Women were followed up on transvaginal ultrasonography to monitor follicular growth, endometrial thickness and evidence of ovulation. Human chorionic gonadotropin 10 000 IU was given i.m. to trigger ovulation when at least one mature follicle measured ≥18 mm at day 14. RESULTS: In all cases, early induction protocol resulted in significantly higher proportion of ovulating patients, thicker endometrium and higher number of follicles 14-17 mm in diameter, ≥ 18 mm in diameter and total number of follicles (P < 0.001 for all comparisons). CONCLUSION: In women with PCOS, early initiation of CC before withdrawal bleeding or during the last days of the luteal phase can achieve a better ovulatory response.
