Lecture 21: Menopause

Question 1

Describe the evolution of menopause

Answer 1

Females experience relatively early onset of reproductive system failure compared to other organs

Question 2

What are the four theories of why menopause occurs;

Answer 2

1) Blessings of modern life
2) Senescence
3) Group Selection
4) Good mother/grandmother theory

Question 3

Describe the theory of senescence;

Answer 3

• To protect the woman from hazards of child birth

- Deterioration of reproductive processes as woman age

Question 4

Describe the theory of group selection;

Answer 4

menopause protects against birth defects causes by age related deterioration of follicle quality (follicles metabolically active, so older they become, the crappier they are)

Question 5

Describe the good mother / grand mother theory;

Answer 5

A pause from reproduction to provide external maternal care of offspring

Evidence suggests improved outcomes for children with grandparents present

Question 6

What is menopause;

Answer 6

The last natural menstrual bleed (represents end of womans reproductive life)

Question 7

When does menopause typically occur?

Answer 7

50-52

Question 8

Why does menopause occur?

Answer 8

Atresia and ovulation result in exhaustion of follicular reserve

Remember, 30 follicles a day enter growth cycle and only 30 are selected for further growth with one becoming dominant

Question 9

What is POF;

Answer 9

Ovarian failure under age of 40 years

Question 10

What is the popcorn hypothesis?

Answer 10

Quality and quantity of follicles decline with age

Question 11

Describe factors that influence timing of menopause;

Answer 11

Smoking
Poor nourishment
age of menarche
maternal age of menopause

All may influence the age of menopause

race doesnt

Question 12

What does smoking do?

Answer 12

Increases the rate of follicle loss

Question 13

Describe the phases of menopause;

Answer 13

Pre-menopause (normal cycles) 40-46
Menopausal transition (46-menopause_
Menopause (last bleed)
Post menopause
Ovarian sénescence
Perimenopause

Question 14

What is perimenopause;

Answer 14

The time from menopausal transition to ovarian senescence

Question 15

What is ovarian senescence?

Answer 15

Absolute end of fertility in ovaries

Question 16

What is a sign that a female may be in the perimenopausal stage?

Answer 16

Menstrual cycle becomes longer (76% 4+ days)

Therefore less likely to be ovulatory

Question 17

What are older women more likely to have?

Answer 17

They are more likely to be anovular (15%)

Question 18

Give a brief overview of perimenopausal changes;

Answer 18

Menopausal transition -> Ovarian senescence

• Erratic hormone fluctuations
• Climacteric (physical and emotional symptoms)
• 5-10% dont experience these transitional symptoms

Question 19

Describe the first sign of perimenopause;

Answer 19

• Follicle level drops below critical threshold (25k)
• Inhibin B levels decline (release by granulosa cells) (part of n. feedback) thus
  = Increased FSH
• Acceleration of follicle loss
  = Shortened follicular phase
  = Increased early follicular estrogen

Question 20

Describe what does changing FSH lead to?

Answer 20

Higher FSH levels during the last decade of reproductive life leads to greater portion of primordial follicles entering the growing pool thus acceleration of follicle depletion.

Question 21

Describe the features of perimenopause;

Answer 21

• Accelerated depletion of follicular reserve
• Irregular cycles
• Anovular
• unpredictable hormone patterns
• contraception is difficult

Question 22

Describe chaning hormone levels during menopause;

Answer 22

Decrease inhibin B
= FSH (10-20x) and LH (4-5x) increase

Oestrogen decrease (80-90%)
Androgen decrease (15%)

Question 23

Can menopause be diagnosed?

Answer 23

No endocrine tests can be done, is retrospective diagnosis

Question 24

What may indicate menopause

Answer 24

45+ who has been anovular for 12 months (98% change of menopause)

Question 25

Describe post menopausal estrogen production

Answer 25

Ovary ceases hormone production therefore all hormone concentrations drop their max conc. and variability (through cycle) decreases.

Most estrogen is from adipose (estriol)

Question 26

Describe estrogen production in post menopausal women;

Answer 26

Extraglandular production

Adipose tissue aromatisation of adrostenedione to estriol

1/10th biological activity of estradiol

Question 27

Brief overview of menopausal symptoms;

Answer 27

Variety of symptoms in response to varying hormone levels
Follow onset of menopausal transition
10% seek help

Question 28

Describe perimenopausal symptoms;

Answer 28

• Vasomotor (hot flush)
• Genitourinary symptoms (vaginal dryness (less secretion)
• Reduction in uterus size and breast density
• Altered bone metabolism
• Blood lipid changes
• Behavioural/ psychological changes (depression, tension)

Question 29

Describe hormone replacement therapy;

Answer 29

Given in severe cases in as little doses and for as short time as possible because can cause;

Breast + uterine cancer
Heart disease
Stroke
Alzheimer’s disease