Pituitary and ovarian response to acute stimulation with LH-RH in normal and anovulatory women

Abstract

The LH FSH estradiol and progesterone responses to acute stimulation with LH-RH were studied in 12 normal women with ovulatory cycles (4 in the initial follicular phase, 4 in the mid-follicular phase and 4 in the late follicular phase) and in two castrated women, two under hormonal contraception, two with ovarian amenorrhea, twelve with central amenorrhea of no detectable origin (6 with normal and 6 with low basal gonadotrophins), eleven anovulatory patients with pseudomenstruation, two with anorexia nervosa, and two with pituitary amenorrhea. Each woman received a rapid i.v. injection of 100 microgram synthetic LH-RH at 9:00 a.m. Serum levels of LH, FSH, estradiol and progesterone were determined by radioimmunoassay in samples collected before and 60, 120, 240 and 480 minutes after injection. The findings were : 1) A significant rise in estradiol and progesterone levels, in addition to LH and FSH elevation, in normal women; 2) A lack of ovarian steroid response in the castrated women and in ovarian amenorrheas, which suggests that the source of steroid response to stimulation is not extragonadal; 3) Significant differences in the responses of the four hormones to LH-RH in the women with central amenorrhea in comparison with the normal group with great variability of results; the steroid response in the presence of a positive LH response might correlate with the severity and/or prognosis of the disorder, a point deserving further study; 4) In anovulatory women with pseudomenstruation, LH responses for the most part normal, and particularly, progesterone responses.

PIP: Simultaneous pituitary and ovarian responses to acute stimulation (100 mcg iv injection) with luteinizing hormone-releasing hormone (LH-RH) in normal women at different times of the menstrual cycle were determined and the results were compared with those obtained in women with anuvulation from different causes. There were 12 normal women, 2 women who had had surgical oophorectomy, 2 who were taking combined hormonal contraceptives, 1 with amenorrhea following pelvic irradiation, 1 with gonadal dysgenesis, and 2 with anorexia nervosa. There were also 12 patients with secondary amenorrhea without detectable pathology. All patients received an iv injection of 100 mcg of synthetic LH-RH. In the normal patients basal LH levels were significantly (p .05) higher on Days 13-14 of the cycle than on Days 4-5. In all 3 phases of the cycle, LH reached peak poststimulation levels within 60 minutes after LH-RH injection. Castrate women showed basal LH levels and LH response profiles similar to normals. There were no estadiol or progesterone responses in this group. Women using hormonal contraception showed low basal levels of both gonadotropins with poststimulation LH response but no follicle stimulating hormone response. Estradiol response in this group was slightly lower and more sustained than in normal women. In patients with ovarian amenorrhea, responses were similar to those in castrated women. In patients with anorexia nervosa findings were normal.