Looks like we were given the same lecture twice, most of this is a rehash but there are some male hypogonadism questions at the end, soz
What is GnRH?
Gonadotrophin releasing hormone
released by hypothalamus
stimulates release of FSH and LH from anterior pituitary
What sort of GnRH pulses stimulate the release of
FSH
LH?
FSH - LOW frequency pulses
LH - HIGH frequency pulses
How long does the menstrual cycle last?
28 - 35 days
What are the two phases of the menstrual cycle?
Follicular phase
Luteal phase
When roughly does ovulation occur?
Around 14 days, midway between follicular and luteal phases
Surge of which hormone triggers ovulation?
LH
What is the dominant hormone in the luteal phase?
Progesterone
Oestradiol peaks when?
Progresterone peaks when?
Oestradiol before ovulation
Progesterone after
Which hormone causes thickening of the endometrium?
Oestrogen
How does oestrogen affect gonadotrophin release in the follicular phase and luteal phase?
Pos feedback follicular
Neg feedback luteal
Which hormone is secreted by the corpus luteum and maintains early pregnancy?
Progesterone
A high serum progesterone level one week on Day 21 indicates what?
Woman has ovulated
Irregular cycles cause ___.
anovulation
Ovulation disorders cause which symptoms?
Oligomenorrhoea (cycles longer than 35 days)
Amenorrhoea (no period)
Issues with which glands cause anovulation?
Hypothalamus
Pituitary
What are the levels of FSH and LH in hypothalamic pituitary failure?
Low
because no GnRH produced
Because no FSH and LH are released in hypothalamic pituitary failure, oestrogen is __.
low
How can oestrogen deficiency be investigated?
Progesterone challenge test
Imitates peak in luteal phase, negative if no menstruation occurs afterwards
How is hypothalamic-pituitary related anovulation treated?
GnRH injections (pulsatile)
OR
Gonadotrophin (LH/FSH) injections
What is the most common endocrine disease in women and causes anovulation with a positive progesterone challenge test?
Polycystic ovary syndrome
What are the three diagnostic criteria for polycystic ovary syndrome?
Oligo/amenorrhoea
Polycystic ovaries
Hyperandrogenism (acne, hirsutism due to increased testosterone)
How is PCOS treated before ovulation is induced?
Weight loss
Lifestyle modification
Folic acid
Rubella immunisation
Why do patients with PCOS take oestrogen tablets e.g Clomid?
Induces ovulation
Apart from oestrogen tablets, what other treatments exist for PCOS?
Gonadotrophin injections
Ovarian drilling?!?!?!?!
What, normally associated with diabetes, is also seen in the majority of PCOS patients?
Insulin resistance
big long list of reasons why, don’t really matter
Which drug is used to address insulin resistance in PCOS?
Metformin
Why does PCOS cause insulin resistance?
High levels of LH causes hyperinsulinaemia for some reason
Insulin lowers level of transporter which mops up testosterone
> Masculinisation (acne, hirsutism)
What are some risks of using drugs like Clomid and gonadotrophin injections to stimulate ovulation?
Ovarian hyperstimulation
Multiple pregnancy (twins are evil)
Ovarian cancer
Multiple pregnancy (twins, triplets) tend to be (premature / late) and can have lots of complications.
premature
complications - cardio, resp, disability
Using ovulation induction for long periods of time has been linked to what?
Ovarian cancer
What is ovarian failure?
Failure to produce new eggs
High FSH and LH, low oestrogen
Amenorrhoea
i.e the menopause
What is premature ovarian failure?
Menopause before the age of 40
Which genetic syndrome causes premature ovarian failure?
Turner syndrome
45 XO
If a person with premature ovarian failure wanted to conceive, how would they go about this?
Combined oral contraceptive pill to replace oestrogen
Egg / embryo replacement because they don’t have any
Counselling
What can cause testicular failure in men?
Klinefelter syndrome
47 XXY
Men with ___ testes may have testicular failure.
undescended
Apart from Klinefelter’s and undescended testes, what can cause testicular failure?
Trauma
What pituitary problem can cause infertility?
Hyperprolactinaemia secondary to a pituitary tumour
What are the tell tale signs of hyperprolactinaemia?
Amenorrhoea
Galactorrhoea
Visual field disruption
What inhibits the release of prolactin normally?
Dopamine
So dopamine antagonists (anti-depressants) may cause hyperprolactinaemia
What is an example of a drug used to treat hyperprolactinaemia?
Dopamine agonist
e.g cabergoline
What is the most important test to determine whether or not a woman is ovulating?
Progesterone challenge test
If she’s not ovulating, then check all the other hormones
Which scan is routine for all women with infertility?
Ultrasound pelvis