Lecture 10: Menopause Flashcards
What is menopause?
The permanent cessation of menstruation (the time when there has been no menstrual periods for 12 consecutive months and no other biological/physiological cause can be identified)
- part of a womans natural ageing process
- ovaries produce lower level of oestrogen and progesterone
- she is therefore unable to get pregnant
What is the definition of climacteric?
Physiological period in a woman’s life during which there is regression of ovarian function
- may result in less periods
- no 12 month cessation yet
What is the menopausal transition?
Time between onset of irregular menses and permanent cessation of menstrutation
-usually 4 years
What is classed as early menopause?
Menopause that occurs under the age of 45
What is premature menopause?
Cessation of menstruation due to depletion of ovarian follicles before the age of 40
-also called premature ovarian failure
What is surgical menopause?
Permanent cessation of menstruation after bilateral oophorectomy
When does physiological menopause usually occur?
Between the ages of 45-55 (average 50yo)
What is pathological menopause?
The gradual or abrupt cessation of menstruation before 40 yo idiopathically
What are the 4 categories in the menopausal phase?
- Pre-menopausal: may be slight changes to FSH/LH levels but cycle is still relatively normal
- Peri-menopausal: loss of oestrogen, causing increase in FSH and LH causing heavy/irregular periods
- Menpause
- Post menopause
What happens in pre-menopause?
The time prior to menopause -typically from ages 40+ -slightly less oestrogen secreted -LH and FSH levels may rise (FSH more) (may be reduced negative feedback) -could result in some reduced fertility
What happens in peri-menopause?
Termed the transition phase (climacteric)
- characterised by the physiological changes associated with the end of reproduction capacity
- follicular phase shortened
- ovulation can be early or absent
- this stage terminates with the completion of menopause
What is post menopause?
Time after which a woman has experienced 12 consecutive months of amenorrhea
How many possible oocytes do we have at menopause?
1000 possible oocytes
-quality of these are poor
Explain the degeneration of ovarian function:
- 100,000s of ova develop
- in reproductive life roughly 400 of the primordial follicles grow into mature follicles and ovulate
- at 45 yo you only have a few primordial follicles that remain to be stimulated by FSH and LH
- production of oestrogen by ovaries decreases as the number of primordial follicles approaches zero
- when oestrogen production falls below a critical value, the oestrogens can no longer inhibit the production of FSH and LH (there is no productionof inhibin)
What is the overall cause of menopause?
Occurs when the ovaries are totally depleted of follicles and no amount of stimulation from gonadotrophins can force them to work
i.e. primary ovarian failure