PITUITARY-OVARIAN RELATIONSHIPS PRECEDING MENOPAUSE .1. CROSS-SECTIONAL STUDY OF SERUM FOLLICLE-STIMULATING-HORMONE, LUTEINIZING-HORMONE, PROLACTIN, ESTRADIOL, AND PROGESTERONE LEVELS

Abstract

Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, estradiol and progesterone concentrations were measured in 58 ovulating women in different age groups (20-29, 34-39, 40-44 and 45-50 yr) at 5-7 day intervals through a single menstrual cycle in 18 postmenopausal women sampled weekly 5-6 times. The over-all hormone patterns were similar in 4 premenopausal groups. However, mean serum FSH levels increased with age; significantly higher concentrations were found in the 40-50 yr group than in the 20-29 yr group. Serum LH levels did not show a similar rise with age, although follicular LH levels in the oldest group were higher than in the 20-29 yr group. Prolactin and estradiol concentrations did not change with age prior to the menopause, but luteal progesterone levels were lower in the 3 older premenopausal groups than in the 20-29 yr group. Postmenopausal women showed elevated FSH and LH, decreased prolactin and negligible estradiol and progesterone levels. There was an over-all significant linear correlation between prolactin and estradiol concentrations. The menopause seems to be preceded by several years of rising gonadotropin, predominantly FSH, levels. During this period, ovarian estrogen production appears to be maintained and ovulation continues, but luteal progesterone levels decline. These premenopausal alterations in pituitary-ovarian relationships probably reflect depletion of ovarian follicles.