Oral contraceptives, menstruation and HRT Flashcards
What is the menopause?
Which phase of the ovarian cycle is lost
Permanent cessation of menstruation
-climacteric: period of transition
Loss of ovarian follicular activity
What is the average age of the menopause?
51 (45-55)
How does menopause normally develop?
You have normal regular cycles every month and then they get longer (oligomenorrhoea) and then this progresses to amenorrhoea
What are the symptoms of the menopause?
Hot flushes Urogenital atrophy and dyspareunia Sleep disturbance Depression Decreased libido Joint pain Symptoms usually diminish/disappear with time
What is dyspareunia?
It is painful to have sex
What hormonal changes occur during the menopause?
There is follicular atresia which leads to low levels of oestradiol and inhibin B, this means that there is less negative feedback so gonadotrophin levels go up
What is the major complication of the menopause?
Osteoporosis
Why does osteoporosis occur in the menopause?
Loss of what
It is caused by oestrogen deficiency- An anabolic hormone so reduced oestrogen will result in osteoporosis
Loss of bone matrix resulting in an increased risk of fracture
What happens to cardiovascular risk due to the menopause?
How do you contorl vasomotor symptoms - hot flushes
Before the menopause it is lower than men but afterwards it’s the same by the age of 70
HRT
What do you give in HRT normally and why?
Oestrogen and progesterone
Oestrogen- endometrial proliferation
There is a risk of endometrial carcinoma so you give progesterone to prevent endometrial hyperplasia.
You don’t have to give progestrogen if they had a hysterectomy
What are the normal ways that HRT is given?
Cyclical- take estradiol every day and for the last 12-14 days take progesterone
or
Everyday take oestrogen and progesterone in small amounts
Why does oestrogen have a low bioavailability?
Extensive first pass metabolism when given orally so high doses needed
How is the problem of the high first pass metabolism dealt with in oral contraceptives?
Oestrogen is given as ethinyl estradiol which is semi-synthetic and the ethinyl group protects the oestrogen
OR Estrone sulphate (conjugated oestrogen)
What is another common way of administering most oestrogens?
Another practical way
Transdermal skin patches
intravaginally
What are side effects of oestrogen?
Breast cancer Coronary heart disease Deep Vein thrombosis Stroke Gallstones
What is tibolone?
Synthetic pro hormone that has oestrogenic, progestogenic and weak androgenic effects
What does tibolone reduce the risk of?
Fracture
What does tibolone increase the risk of?
Stroke and breast cancer
What is raloxifene?
Selective oestrogen receptor modulator (SERM)
How does raloxifene work?
It is tissue selective
In bone- it has oestrogenic effects- reduces the risk of fracture
In breast and uterus- it has anti-oestrogenic effects- reduces risk of breast cancer
What is raloxifine associated with increased risk of? What does it not deal with
Fatal stoke and VTE
Vasomotor symptoms
What does tamoxifen do?
It is anti-oestrogenic on breast and is used to treat oestrogen dependent breast tumours and metastatic breast cancers
What is premature ovarian insufficiency?
Menopause occurring before the age of 40
What can cause premature ovarian insufficiency?
Autoimmune
Surgery
Chemotherapy
Radiation
What forms of oestrogen and progesterone are used in oral contraceptive?
Oestrogen- ethinyl oestradiol
Progesterone- Levonorgestrel or norethisterone
How does oral contraceptive work?
Suppress ovulation
-Suppression of negative feedback at hypothalamus and pituitary (both e and p do this)
-Progesterone also thickens the cervical mucus which makes it harder for sperm to get through
You take it for 21 days and stop for 7
When is progesterone only contraceptive used?
How is it taken
When use of oestrogen is contraindicated- e.g. if there is a risk of thrombosis because oestrogen is a procoagulant
Must be taken at the same time each day
- Short half-life
- Short duration of action
Long acting preparations may be given via an intra-uterine system
What is MIRENA?
Intra-uterine progesterone device
What are the three types of emergency (post coital) contraception?
Copper IUD
Levonorgestrel
Ulipristal
How does a copper IUD work?
Within time frame
Affects sperms viability and function and inhibits fertilisation
5 up to 7 days after unprotected
What is levonorgestrel?
High dose of progesterone
within 72 hours
How does ulipristal work?
Anti-prostegin activity
Delays ovulation by 5 days
Impairs implantation
up to 120 hours after intercourse
