A New Superagonist of GnRH for Inhibition of Ovulation in Women

This paper presents the initial results from a study that used a new superagonist of gonadotrophin-releasing hormone (GnRH), naferelin acetate, for the inhibition of ovulation. The superagonist was administered by nasal spray daily for 12 weeks to 20 women with regular menstrual periods. Radioimmunoactive estradiol and progesterone were assayed weekly, and there were regular check ups and daily recordings of basal body temperature. None of the subjects had a normal ovulatory menstrual cycle during 57 treatment months. During the 1st 8 weeks, 7 women had menstrual-like bleeding, 8 had oligomenorrhea, and 5 were amenorrheic. No pregnancies occurred during the study, nor were there any clinical symptoms or signs of estrogen deficiency. These preliminary findings suggest that nafarelin is a potent antifertility drug with potential use for contraception. The antireproductive properties of the agonist are also of interest for treatment of tumors, gynecologic disorders such as endometriosis and polycystic ovarian disease, and precocious puberty.