Long-term intranasal luteinizing hormone-releasing hormone agonist treatment for contraception in women.

Fifty-one female volunteers used a superactive stimulatory luteinizing hormone-releasing hormone (LH-RH) analog for suppression of ovulation for 3 to 12 months. The potent LH-RH agonist D-Ser(TBU)6-EA10-LH-RH was administered intranasally once daily in a dose of 400 or 600 micrograms. No pregnancies occurred during the 283 treatment months. Severe bleeding disturbances were not observed during the long-term treatment. No signs of hyperplastic changes were found in endometrial biopsies. There were no serious side effects. Ovulation promptly returned after cessation of treatment even in women with amenorrhea during treatment periods of 1 year or more. Thus, long-term LH-RH agonist treatment proved to be a safe, effective, and rapidly reversible new method for peptide contraception.