[Effect of the GnRH analog buserelin on sex hormone serum level in relation to treatment onset and duration]

Cyclic and individualized administration of gonadotropin-releasing hormone agonists plus progestogens: an alternative protocol for contraception

Twenty-one women presenting with different diseases, with absolute or relative contraindications to hormonal contraception or the use of intrauterine devices, received 300-600 micrograms/day buserelin intranasally from the 1st to the 21st day, and 5 mg/day norethisterone acetate orally from the 16th to the 23rd day of the cycle for a total of 245 cycles. Serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol and testosterone were determined on days 3-5 and 13-15 of the cycle, while progesterone determinations and ovarian sonography were performed during the second half of the cycle. According to progesterone values, 92.7% of the treatment cycles were anovulatory, while in one cycle pregnancy was detected (0.4%). Values of serum LH, FSH and estradiol were low, and in most of the cycles ovarian follicular development was limited to follicles < or = 11 mm. In 21 treatment cycles (9%), statistically significant increases in FSH (p < 0.0001) and LH (p < 0.02), as well as ovarian proliferation to preovulatory follicles or luteinized follicles, were found. It appears that in spite of the high cost of medication and monitoring of patients, this regimen could be useful as an alternative in cases where other forms of contraception are contraindicated or have failed.