Pituitary‐ovarian Function Before, During and After the Menopause: A Longitudinal Study

Abstract

The excretion of FSH, LH, oestrogens and pregnanediol was monitored once weekly in urine samples collected from eight peri-menopausal women aged 44-55 years (median, 52 years). Observations were commenced between 5 and 15 weeks before the menopause and were continued for 22-30 weeks after final menstruation. Amenorrhoea of greater than 2 years duration in association with a persistent elevation in gonadotrophin output was considered proof of the post-menopausal state. No clear hormonal change occurred at the time of the menopause. During the peri-menopause there is a transition from the regular ovulatory cycles of pre-menopausal women to the unvarying high gonadotrophin and low oestrogen excretion which is generally regarded as being characteristic of post-menopausal women. In the group studied, post-menopausal levels of FSH and LH were common before and episodes of high oestrogen excretion were not uncommon after final menstruation. Menstrual failure appeared to occur spontaneously at some stage during the transition from the pre- to the post-menopausal state, and not to be associated with its conclusion. From the hormonal point of view the immediately post-menopausal period could not be distinguished from the long cycles of peri-menopausal women. This suggests that an endometrial rather than a hormonal event might determine the time at which menstruation stops during the menopausal transition.

The ReSTAGE Collaboration: defining optimal bleeding criteria for onset of early menopausal transition

“…Selection of this marker as the bleeding criterion for onset of the early menopausal transition defines the early transition as a phenomenon of the late thirties and early forties. Such timing is consistent with data on ovarian aging (27)(28)(29), with studies suggesting an increase in the rate of atresia of ovarian follicles at age 37 (30) and with studies showing an inflection point for the increase in population-averaged FSH levels at a similar age (31). Using a marker comparable to the persistent >6 day difference marker, Gracia and colleagues found statistically significant differences in serum inhibin-B and FSH levels between women who reported this relatively subtle change in menstrual cycle length and women who did not (25).…”

The Clinical Biochemistry of the Menopause and Hormone Replacement Therapy

“…Metcalf et al 16 highlighted the fact that the fluctuating hormone concentrations of the menopausal transition did not stop at the menopause, elevated oestrogen excretion occurred in five of eight women during the first 6 postmenopausal months. Urinary LH and FSH excretion was no different in the first 5 weeks after the menopause compared to before it, although by [15][16][17][18][19][20] weeks, gonadotrophin concentrations were slightly higher.…”

“…Urinary LH and FSH excretion was no different in the first 5 weeks after the menopause compared to before it, although by [15][16][17][18][19][20] weeks, gonadotrophin concentrations were slightly higher. The menopause was associated with only one clear hormonal change-invariably low pregnanediol excretion in the 6 months that followed implying cessation of ovulation.…”

Effect of menopause on platelet activation markers determined by flow cytometry

“…Post-menopause was defined as amenorrhea for the past 2 years [19]. Special care was taken while recruiting subjects, and diagnosed cases of diabetes mellitus, hypertension, hyperlipidemias, chronic medical illness, menstruation on the day of study for pre-menopausal women, and previous thromboembolic phenomena were excluded from the study.…”