disorders of ovulaton Flashcards
What is Kisspeptin
A GnRH secretagogue, at the apex of the reproductive axis in the hypothalamus.
highly responsive to oestrogen
What are some tests to diagnose ovulation
Day 21 progesterone blood test
LH detection kits: urinary kits, over counter
Transvaginal pelvic ultrasound is done from day 10, alternate days to show the developing follicle size.
What is Amenorrhoea
Lack of period for more than 6 months
primary- never had a period (no menarche)
secondary- has menstruated before
What is oligomenorrhoea
- irregular periods
- usually 6 weeks apart
What is polymenorrhoea
Periods occurring less than 3 weeks apart
What are hypothalamic causes of ovulation problems
GnRH deficiency (Kallmann’s syndrome)
‘Functional’ hypothalamic amenorrhoea
- weight loss/ stress-related
- anorexia nervosa/ bulimia
What are some pituitary causes of ovulation problems
lack of FSH and LH
- pituitary tumours
- post pituitary surgery/ radiotherapy
What are some ovarian causes of ovulation problems
Premature ovarian insufficiency
- chromosomal e.g. turners syndrome
- autoimmune
- latrogenic ( post-surgery/ chemotherapy)
hyperandrogenism
- POCS
- congenital adrenal hyperplasia
What is Hirsutism
Androgen-dependant hirsutism is excess body hair in a male distribution
What are the commonest causes of hirsutism
PCOS or idiopathic
When should you worry about Hirsutism
Sudden onset of severe symptoms
Virilization: Frontal balding, deepening of voice, male-type muscle mass and clitoromegaly
-possible Cushing’s syndrome
What are the clinical features of PCOS
Hyperandrogenism
-hirsutism, acne
chronic oligomenorrhoea/ amenorrhoea
- less than 9 or 9 periods per year
- subfertility
obesity (but 25% of women with PCOS are “lean”)
What are the hormonal abnormalities in PCOS
Raised baseline LH and normal FSH levels, 3:1
raised androgens and free testosterone
reduced sex hormone-binding globulin (SHBG)
Oestrogen usually normal
What is SHBG
Sex Hormone Binding Globulin
produced by the liver
binds testosterone and oestradiol
SHBG increased by oestrogens and decreased by testosterone.
What are the reproductive effects of PCOS
15% of all causes of infertility is due to a lack of ovulation and 80% of lack of ovulation is due to PCOS
there is an increase in miscarriages and gestational diabetes
How do PCOS and endometrial cancer link
in PCOS Irregular periods and high oestrogen levels can lead to endometrial hyperplasia which is a risk factor for endometrial cancer (also type 2 diabetes and obesity)
What lifestyle modifications are important for PCOS
Diet and exercise, and stop smoking. results in:
- decreased insulin resistance
- increased SHBG
- decreased free testo
- improved fertility and better metabolic syndrome factors
What is another form of treatment for PCOS
Combined oral contraceptives
- increases SHBG and thus decreases free testosterone
- decreases LH and FSH, therefore ovarian stim regulates the cycle and decreases endometrial hyperplasia.
may cause weight gain, venous thrombosis, adverse effects on metabolic risk factors.
What are some examples of anti-androgens and why are they used
Cyproterone acetate (oral tablet) spironolactone (anti-mineralocorticoid and anti-androgen properties)
They can be used with COCP’s if COCP has been insufficient but must be taken with secure contraception because they have a teratogenic effect.
How does metformin work and why would it be used for PCOS
decreases insulin resistance, insulin levels and ovarian androgen production
may help with weight loss and diabetic prevention, used because it helps increase ovulation, (with clomifene) safe in pregnancy
less helpful for hirsutism and oligomenorrhoea
How does primary ovarian insufficiency or premature menopause present
presents as primary or secondary amenorrhoea
What is the aetiology for primary ovarian insufficiency
Autoimmunity: may be associated with other autoimmune endocrine conditions
X chromosomal abnormalities
e.g. Turners syndrome and fragile X syndrome
iatrogenic e.g. surgery, radio or chemo
What are the investigations for primary ovarian insufficiency
Herstory/exam
look for an increase in LH/ FSH levels
consider pelvic USS
consider screening for autoimmune endocrine disease (ThyroidFT, glucose and cortisol)
How is primary ovarian insufficiency managed
Psychological support
HRT (hormone replacement therapy)
Monitor bone density via DEXA scan
fertility- IVF with donor egg.
What is turners syndrome and how does it present
Complete or partial X monosomy in some/ all cells
- 50% of cases will have just 1 X chromosome
- rest: partial absence of X
presentation: may be diagnosed in the neonate, may present with short stature in childhood
primary or secondary amenorrhoea.
What are associated problems with turners syndrome
- short stature, consider GH treatment
- CV system, coarctation of the aorta, bicuspid aortic valve, hypertension (adults)
- Renal (congenital abnormalities)
- Metabolic syndrome
- hypothyroidism
- ears/ hearing problems
- osteoporosis (lack of HRT)
What are some features of congenital adrenal hyperplasia (CAH)
- cortisol deficiency
- may have aldosterone deficiency
- androgen excess
- depends on the degree of enzyme deficiency
How does CAH present in childhood
salt wasting: hypovolaemia, shock
virilisation: ambiguous genitalia in girls and early virilisation in boys
- precocious puberty
- abnormal growth
How does CAH present in adulthood
- hirsutism
- oligo/ amenorrhoea
- acne
- subfertility
- similar to PCOS presentation
What are some treatments for CAH
Gluco/ mineralocorticoid replacement (hydrocortisone and fludrocortisone
excess glucocorticoids may inhibit growth
surgical management for ambiguous genitalia
