PERIMENOPAUSAL PATTERNS OF GONADOTROPINS, IMMUNOREACTIVE INHIBIN, ESTRADIOL AND PROGESTERONE

In order to assess the possible role of circulating immunoreactive inh ibin (INH) during the menopausal transition, two groups of subjects we re studied. Four were normal volunteers, three of whom had developed t heir first symptoms of cycle irregularity at age 45-46 years, the four th being aged 37, a volunteer for a study involving daily blood sampli ng found to have a transient rise in serum follicle stimulating hormon e (FSH). Six were patients with anovulatory infertility, aged 34-44 ye ars, found to have transitory ovarian failure during attempts at ovula tion induction. Intermittent blood samples were obtained for radioimmu noassay of serum FSH, luteinizing hormone (LH), INH, oestradiol (E2), and progesterone. Abrupt changes were observed, with transient elevati ons of FSH and LH and decreases of INH and E2 into the postmenopausal range, followed by levels more characteristic of reproductive-aged wom en. It was concluded that typical postmenopausal hormone patterns may occur at the time of entry into the normal menopausal transition, and in some women with anovulatory infertility, but may be completely and relatively abruptly reversible. Elevation of serum FSH into the postme nopausal range, with undetectable INH concentrations, does not provide reliable evidence that the menopause (or permanent ovarian failure) h as occurred. INH contributes to elevations of serum FSH during the men opausal transition.