Urinary beta-FSH subunit concentrations in perimenopausal and postmenopausal women: a biomarker for ovarian reserve

OBJECTIVE

The purpose of this study was to develop an integrative assessment of pituitary follicle-stimulating hormone (FSH) secretion and to validate these measurements in a population of perimenopausal (PERI) and postmenopausal (POST) women.

DESIGN

In this cross-sectional study, 170 POST and 20 PERI women collected first-void morning urine samples and had a single blood sample drawn on the same day. For comparison, 11 midreproductive-aged women had urine samples collected for one menstrual cycle. In addition, one 48.5-year-old woman collected daily urine samples for 4 consecutive years during her menopausal transition. Urine samples were assayed for estrone glucuronide (E1G) and pregnanediol-3-glucuronide (PdG) and were normalized to creatinine. An ELISA assay was developed for measurement of the free beta-FSH subunit in urine.

RESULTS

Mean age (+/- SD) of the PERI and POST women were 48.1 +/- 3.0 and 52.8 +/- 4.1 years, respectively. Mean serum FSH levels were 9.5 +/- 5.8 and 79.3 +/- 32 IU/L (P < 0.001) in the PERI and POST women. Mean urinary beta-FSH/Cr for the PERI were 1.8 +/- 1.2 ng/mg; for the POST, 9.3 +/- 4.5 ng/mg (P < 0.001). Mean estradiol, E1G/Cr, and PdG/Cr levels were also significantly different between the two groups. There was a high correlation between serum FSH and urinary beta-FSH/Cr for the PERI (r = 0.584, P = 0.007) and POST (r = 0.54, P < 0.001), with minimal overlap in the urinary beta-FSH/Cr levels between the PERI and POST groups. A significant correlation between PdG/Cr and urinary beta-FSH/Cr was observed for POST (r = 0.581, P = 0.002). No correlation was seen between urinary beta-FSH/Cr and E1G/Cr or estradiol levels. In the perimenopausal participant, who collected 4 years of daily urine samples, urinary beta-FSH/Cr levels progressively increased during the follicular phase and, by the fourth year, there were persistent, almost tonically high elevations of beta-FSH/Cr in the urine.

CONCLUSIONS

Urinary beta-FSH subunit measurements are a useful marker for monitoring ovarian function during the menopausal transition. Urinary free beta-FSH subunit concentrations reflect pituitary FSH secretion and serve as a biomarker for ovarian reserve.

Hypercalciuria and urinary saturation measurements in climacteric women

Fifteen percent (20/130) of a group of climacteric women on diets of their choice had urinary calcium (Ca) levels exceeding 4 mg/kg per day. Most of these hypercalciuric subjects had a daily Ca intake of 0.4-0.5 g. Their bone turnover rates were raised and high Ca absorption was observed in 4 cases. Serum Ca and total protein and glomerular filtration rates were normal in all the hypercalciuric patients. The calcium/creatinine (Ca/Cr) ratio (mg l-1/mg l-1, fasting, 09:00-10:00 h) was measured in 72 climacteric women, 35 of whom (49%) had ratios > 0.1. The latter defines a relative hypercalciuria as compared with premenopausal Ca excretion levels. Only 5 of the 35 subjects had calciuria levels above 4 mg/kg per day. The Ca/Cr ratio cannot replace daily urinary Ca measurements for the screening of subjects in whom calciuria may exceed net Ca absorption. Urinary saturation measurements were carried out in 70 women. Supersaturation was observed only in the case of Ca oxalate (CaOx) among several calcium salts usually found in urinary stones. CaOx supersaturation was observed in 95% of the hypercalciuric subjects and in 48% of the rest of the women investigated. The relatively high frequency of CaOx supersaturation can be attributed in part to the decreased excretion of citrate associated with ovarian failure. Oestrogen replacement therapy increased citrate excretion and lowered the level of CaOx supersaturation. Ca supplementation (1 g Ca/day) reduced the degree of supersaturation as a result of the concurrent reduction in oxalate excretion.

[Treatment of climacteric syndrome with new gengnian prescriptions]

It was found by the observations of clinical treatment that the three indexes of epinephrine(E), norepinephrine(NE) and dopamine(D) of urinary catecholamine(CA) increased (P less than 0.001, P less than 0.05 and P less than 0.001) for the climacteric patients who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat of the heart, and the urinary 17-hydroxycorticosteroid (17-OHCS) increased (P less than 0.001) for the patients who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat of the liver. Both the three indexes and urinary 17-OHCS increased for the two groups (P less than 0.01). However, for all the above groups who suffered from the deficiency of Yin leading to the hyperactivity of the internal heat, the NE/E ratio was larger than the normal ratio, which stands for the level of central catecholamine. After the treatment with new Gengnian prescriptions, the clinical symptoms of the patients were improved, and in the meantime urinary CA. 17-OHCS and NE/E were decreased. The total efficiency was 89.2%. The principle of treatment with this prescription may be due to the fact that the level of central catecholamine decreased so that the excessive excitation of sympathetics-adrenocortical system and sympathetics-adrenocortical system was restrained.

Urinary excretion of prostacyclin and thromboxane metabolites in climacteric women: effect of estrogen-progestin replacement therapy

To study the role of vasodilatory prostacyclin and vasoconstrictory thromboxane A2 in climacteric vascular instabilities, overnight urine samples were collected from sixteen women suffering from hot flushes and sweating before, during and after the six months' cyclic estradiol-desogestrel therapy as well as from ten non-climacteric control women. The urine was assayed for 6-keto-PGF1a and 2,3-dinor-6-keto-PGF1a (metabolites of prostacyclin) as well as for thromboxane B2 and 2,3-dinor-thromboxane B2 (metabolites of thromboxane A2) by means of HPLC and radioimmunoassay. No difference was seen in baseline prostaroid output between the climacteric and non-climacteric study groups. Furthermore, no relation was observed between individual prostanoid excretion and severity of vasomotor symptoms before replacement therapy. The replacement therapy abolished or markedly alleviated hot flushes and sweating, but prostanoid output did not change. Our data imply that climacteric symptoms are not accompanied by changes in the production of prostacyclin and thromboxane A2.

[Changes in urinary NAG activity in patients with climacteric syndrome treated with estrogens]

The behaviour of urinary NAG activity was studied in patients during menopause, some of whom were given estrogen therapy due to severe vasomotor symptoms (hot flushes etc.). One group of these patients revealed slightly higher than normal blood pressure. A second group had slight arterial hypertension and pancreatic diabetes. The third group consisted of apparently healthy menopausal women. The significant increase in enzymuria in the first two groups suggests that blood pressure should be carefully checked before starting estrogen therapy. Furthermore this treatment should be given very cautiously and under constant surveillance in the presence of slight hypertension. In patients with diabetes or more severe hypertension, estrogens should never be given.

Qualitative differences in gonadotrophic extracts from urine of postmenopausal women

1. A gonadotrophic preparation made from post-menopausal human urine with tannic acid had more activity on the mouse uterus than would be predicted from the results of the test on the prostate of the hypophysectomized rat.

2. In one experiment, when gonadotrophic principles were adsorbed on kaolin at pH 6 from a very concentrated solution of post-menopausal gonadotrophin in distilled water, even larger quantitative differences were found in the results of these two tests.

3. There was no significant deviation of the dose-response curves from parallelism in either test.

4. The data suggest that there is more than one gonadotrophin in post-menopausal urine.

Urinary excretion of pregnanediol in post-menopausal women and men during prolonged daily administration of progesterone

Progesterone (50 mg/day) was administered by intramuscular injection to six intact post-menopausal women and to one man for periods of 13–20 days, and by mouth to one intact post-menopausal woman for 15 days. Determinations of the daily urinary excretion of pregnanediol by these subjects gave results in marked contrast to those of Sommerville & Marrian [1950].