Oral contraceptives, menstruation and HRT Flashcards
What is the menopause?
Permanent cessation of menstruation
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?
It is caused by oestrogen deficiency- An anabolic hormone so reduced oestrogen will result in osteoporosis
What happens to cardiovascular risk due to the menopause?
Before the menopause it is lower than men but afterwards it’s the same
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.
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
What is another common way of administering most oestrogens?
Transdermal skin patches
What are side effects of oestrogen?
Breast cancer
Venous thromboembolism
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?
Fatal stoke and VTE
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?
Suppression of 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?
When use of oestrogen is contraindicated- e.g. if there is a risk of thrombosis because oestrogen is a procoagulant
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?
Affects sperms viability and function and inhibits fertilisation
What is levonorgestrel?
High dose of progesterone
How does ulipristal work?
Anti-prostegin activity
Delays ovulation by 5 days
Impairs implantation
