1. Menopause: a natural event
Henry Burger

2. Relationships between different time periods surrounding the menopause
Final menstrual period (FMP)
Menopause
Postmenopause
Perimenopause
Menopausal transition
Climacteric
Mean age
51 years
1 year later
International Position Paper: Women’s Health and Menopause, NIH (2002)

3. Ovarian follicle numbers with age
Women in Block's
study
100000 B
Women from the
present study with regular menses B
10000 B B
1000 J
Postmenopausal
women F F
Primordial follicles/ovary B
100 F
Perimenopausal
women F F 10 F F 1 10 20 30 40 50 60
Age (years)
Richardson et al. JCEM 1987

4. Hypothalamo-pituitary ovarian axis
Hypothalamus
Feedback
hormones
GnRH
Steroids
Pituitary
Gonadotropins:
- LH, FSH
Inhibin
Ovary

5. Relationships between FSH and inhibin B
4.5
< 40 years of age
4.0
> 40 years of age
3.5
3.0
Log (FSH)
2.5
2.0
1.5
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Log (inhibin B)
Burger HG et al. Climacteric 2000

6. Geometric mean annual hormone levels relative to date of final menses
300
120
250
100
200 80
150 60
Estradiol (pmol/l)
FSH (IU/l)
100 40 50 20 -4 -3 -2 -1 1 2 3 4 5 60 60 50 50 40 40 30 30
Inhibin B (ng/l)
Inhibin A (ng/l) 20 20 * 10
(InhB)
(InhA)
41%
36%
71%
43%
62%
57%
80%
65%
80%
78%
94% 10 -4 -3 -2 -1 1 2 3 4 5
Years around menopause
* Percent of samples with undetectable inhibin
Burger HG et al. JCEM 1999

7. Androgens in the menopausal transition
In normal women, there is a 50% decrease in circulating concentrations of testosterone and dehydroepiandrosterone sulfate (DHEAS) from age 20 to age 451,2
There is little if any decline in testosterone during the transition2,3
DHEAS levels continue to fall with age, with no specific association with the transition
The medical ‘myth’ that menopause is associated with an acute drop in androgens does not appear to be tenable any longer
1Zumoff 1995, 2Davison 2005; 3Burger 2000

8. Other endocrine features
Loss of LH response to an estradiol challenge in the perimenopause1,2
Predominant circulating estrogen in reproductive life is estradiol, secreted by the ovary; postmenopausally it is estrone, produced by peripheral androgen aromatization3
Anti-Müllerian hormone (also called Müllerian inhibiting substance), a member of the TGF super family and a product of preantral and small antral follicles, is under investigation as a marker for the size of the ovarian follicle pool4 and a promising predictor for the occurrence of the transition5
1Van Look 1977; 2Weiss 2004; 3Maroulis 1976; 4Visser 2006; 5van Rooij 2004