Menopause Flashcards
Why do we go through menopause?
We survive beyond our reproductive years. Only a fixed number of follicles.
Senescence - protect the ageing woman from the hazards of child birth.
Menopause protects human gene pool against birth defects due to age-related increase in chromosomal abnormalities.
A pause from reproduction to provide extended maternal care of offspring - grandmother effect
When does menopause occur?
The menopause is the consequence of the ovaries running out of follicles, and occurs between 50 and 52 years of age.
• Defined by the state of the uterus.
• The last episode of natural menstrual bleeding signifies the end of a woman’s reproductive life and is referred to as the menopause (men – month, pauo – to stop)
• Atresia and ovulation (~400 follicles lost from puberty to menopause) result in exhaustion of the follicular reserve.
What is premature ovarian failure?
Causes women to go through menopause in their 30s.
What usually occurs 10 years before menopause?
Last baby
What happens to the quality of the follicles as we age?
They decrease. As the quantity decreases so too does the quality.
What alters the age of menopause?
In well-nourished populations, its timing is independent of racial background.
Poorly-nourished women have earlier menopause, women who smoke have earlier menopause (1-2 years).
Parity and marital status do not appear to influence the timing of the menopause.
Mothers and daughters have a similar age at menopause.
What are the phases of menopause?
Premenopause - regular menstruation (until 46)
Menopausal transition - 46-52 irregular menstruation.
Post menopause - the last menstruation. Ovarian still functions for another year.
Ovarian senescence - 1 year after menopause
Perimenopause is from the menopausual transition to the ovarian senescence. Some follicles may be present but they are not responding to normal stimuli.
What is perimenopause?
Perimenopause is from the menopausual transition to the ovarian senescence.
What perimenopausal changes occur?
Perimenopause is the time of erratic hormone fluctuations which starts at beginning of menopausal transition and continues through to ovarian senescence. The term climacteric relates to physical and emotional symptoms associated with perimenopause.
5-10% have no problems.
Follicle levels reduce below a critical threshold (~25,000 follicles)
• Inhibin B levels begin to decline (inhibin B is produced by granulosa cells of primary follicles)
• Inhibin has negative feedback on FSH, so FSH levels rise, results in:
o Shortened follicular phase
o Increased early follicular oestrogen
Acceleration of follicle loss (women at ~40)
The higher plasma levels of FSH during perimenopause stimulate a greater proportion of primordial follicles to enter the growing pool, which accelerates the depletion of the primordial reserve (instead of ~20-40/day, get ~80/day follicles recruited instead).
• Higher chance of more than one dominant follicle
• So higher chance of twining.
What are the features of perimenopause?
Accelerated depletion of follicular reserve
Irregular longer cycles
Annovulatory cycles are common
Gonadotrophins often elevated (especially FSH)
Oestrogen levels are often high (early perimenopause) but are sometimes low (late perimenopause and low after menopause)
Unpredictable hormone patterns
Ovulation is always possible
Contraception is difficult
What are the hormone levels before and after menopause?
Inhibin B decreases and FSH increases. LH also increases.
After menopause - estrogen and androgens decrease.
How can you determine if someone has gone through menopause?
No simple endocrine test (maybe AMH, FSH) to recognise the time when menopause occurs or to confirm with confidence that it has occurred, and is usually defined retrospectively.
It can be stated that a woman over 45 years of age who has had amenorrhoea for at least 12 months is highly unlikely to ovulate again and is very probably (98%) postmenopausal.
Marked fluctuations in hormone levels, including oestrogen, can continue more than six months.
Some follicles may be left, however, they may be nonresponsive (popcorn hypothesis).
By ~one year after the menopause, ovary has essentially ceased producing hormones (ovarian senescence).
What is the source of estrogen following menopause?
One year following menopause the production of estrogen decreases and there is less variability in production. No estrodiol.
Oestrogen now occurs from extraglandular production, mainly from aromatisation in stromal cells of adipose tissue of androstenedione secreted by adrenal cortex.
Oestrone is product of aromatisation and while some of it is converted to oestradiol, it is predominant oestrogen of the postmenopausal years.
Androstenedione from the adrenal glands foes into the adipose tissue and is aromatized into estrone.
What are the perimenopausal symptoms?
Most women experience variety of clinical symptoms of oestrogen (and perhaps progesterone) deprivation during perimenopause.
These symptoms usually follow onset of menopausal transition but they may precede it and they sometimes continue for a time after menopause.
Most women manage menopause by themselves, but ~10% seek medical help to deal with the symptoms.
Main 3: vaginal dryness, hot flushes, Night sweats
Vasomotor (vascular instability causes by fluctuating estrogen)
• Hot flushes
• Night sweats
• Often associated with palpitations, weakness, faintness
Genitourinary symptoms (vaginal dryness due to reduced estrogen)
• Atrophic changes
• Decline in epithelial growth and vaginal lining elasticity
• Reduction in vaginal lubrication
• Rise in pH of vaginal fluids
• Dyspareunia, incontinence, urethritis, recurrent urinary infections
Reduction in size of uterus and breasts (due to reduced estrogen)
Bone metabolism
• Increased catabolism
• Osteoporosis
Blood lipid changes
Behavioural/psychological changes
• Depression, tension, anxiety, mental confusion
• Loss of libido
What can be used to treat the symptoms of menopause?
Hormone Replacement Therapy
Most of these symptoms of the menopause may be prevented or arrested by oestrogen treatment.
There is no uniform agreement about safety and advisability of using oestrogen therapy in postmenopausal women. he increased exposure to estrogen is protective against osteoporosis but increases the risk of breast and uterine cancer, heart disease, stroke and Alzheimers disease.
HRT remains an appropriate treatment for women with moderate to severe menopausal symptoms
HRT should be at the lowest dose for the shortest time necessary to control symptoms
