T2 L6: Disorders of ovulation Flashcards
What is the role of kisspeptin in ovulation?
It stimulates the secretion of GnRH. It’s found at the apex of the reproductive axis in the hypothalamus
Kisspeptin neurones are very responsive to oestrogen
What is Amenorrhoea?
Lack of period for more than 6 months
Primary amenorrhoea- has never had a period (never went through menarche)
Secondary amenorrhoea- has menstruated before
What is Oligomenorrhoea?
Irregular periods
Usually occurring 6 weeks apart
What is Polymenorrhoea?
Period occurring less than 3 weeks apart
What causes ovulation problems?
Hypothalamus (lack of GnRH)
Pituitary (lack of FSH and LH)
Ovary
Hyperandrogenism
What is anosmia?
Inability to smell
What are some Hypothalamic ovulation problems?
Hypothalamus (lack of GnRH)
- Kallmann’s syndrome (GnRH deficiency)
- Functional hypothalamic amenorrhoea caused by weight loss, stress, excessive exercise, anorexia
What are some Pituitary ovulation problems?
Pituitary (lack of FSH and LH)
- pituitary tumours Eg. Prolactinoma
- Post pituitary surgery/radiotherapy
What are some ovary associated ovulation problems?
Ovary
-Premature ovarian insufficiency caused by chromosomal abnormalities like Turner syndrome, autoimmune, or iatrogenic
What are some hyperandrogenism ovulation problems?
Hyperandrogenism
- Polycystic ovarian syndrome (commonest cause)
- Congenital adrenal hyperplasia
What is Hirsutism?
Excessive hair in a male distribution
Not androgen-independent hair growth (Hypertrichosis) or familial/racial hair growth
What is Hypertrichosis?
Excessive hair growth over and above the normal for the age, sex and race of an individual
What can cause Hirsutism?
PCOS (95%)
Non-classical congenital adrenal hyperplasia (CAH)
Cushing’s syndrome
Adrenal/ovarian tumour
How prevalent is PCOS?
5-10% of women
What are some clinical features of PCOS?
- Hyperandrogenism (Hirsutism and acne)
- Chronic oligomenorrhoea/ amenorrhoea
- Obesity
What is a USS appearance of polycystic ovaries?
> 10 subcapsular follicles 2-8mm in diameter arranged around a thickened ovarian stroma
What are some hormonal abnormalities in PCOS?
- Raised baseline LH levels and normal FSH
- Raised androgens and free testosterone
- Reduced sex hormone binding globin (SHBG)
- Oestrogen is usually normal
What is sex hormone binding globin (SHBG)?
It binds to testosterone and oestradiol
It’s produced by the liver
If testosterone is found, it’s inactive. Levels of SHBG are increased by oestrogens and decreased by testosterone
How does PCOS affect metabolic syndrome?
- Insulin resistance
- Impaired glucose tolerance
- Dyslipidaemia
- Vascular dysfunction
What are the reproductive effects of PCOS?
- 80% lack ovulation
- Increased risk of miscarriage
- Increased risk of gestational diabetes
How does PCOS increase the risk of endometrial cancer?
Because the patients are not ovulating but the levels of oestrogen are high causing endometrial hyperplasia and cancer
Endometrial cancer is also associated with T2 diabetes and obesity
What are the effects of lifestyle changes like diet, exercise and stopping smoking in PCOS?
- Decreased insulin resistance
- Increased SHBG
- Decreased free testosterone
- Improved fertility
- Improved metabolic syndrome risk factors
What effect does a combined oral contraceptive have on PCOS?
- Increases SHBG and thus decreases free testosterone
- Decreases LH and FSH which decreases ovarian stimulation
- Regulates cycle and decreases endometrial hyperplasia
May cause weight gain, venous thrombosis, adverse effects on metabolic risk factors
Why is Cyproterone Acetate used to treat PCOS symptoms?
It’s an oral pill that inhibits binding of testosterone and 5 alpha dihydrotestosterone to androgen receptors
It acts on the androgen imbalance
Why is Spironolactone used to treat PCOS symptoms?
It has anti-mineralocorticoid and anti-androgen properties
How is Insulin resistance treated in PCOS and why?
With Metformin
- It decreases insulin resistance, insulin levels, and ovarian androgen production
- It may help with weight loss/diabetes prevention
- May increase ovulation
What is the presentation of primary ovarian insufficiency?
Primary or secondary amenorrhoea
Secondary is associated with hot flushes and sweats
What is primary ovarian insufficiency also known as?
Premature ovarian failure
Premature menopause
What is the cause of primary ovarian insufficiency?
- Autoimmune associates with other endocrine conditions
- X chromosome abnormalities like Turner syndrome of Fragile X
- Genetic predisposition
- Iatrogenic causes like surgery, radiotherapy or chemotherapy
How is premature ovarian failure managed?
- Psychological support
- Hormone replacement therapy
- Monitor bone density
- Fertility - IVF with donor egg
What investigations are done to see if someone has premature ovarian failure?
- History/examination
- Increased LH and FSH
- Pelvic ultrasound
- Screen for autoimmune endocrine diseases
What are the presentations of Turner syndrome?
- May be diagnosed as a neonate
- Short stature in childhood
- Primary or secondary amenorrhoea
What are some medical problems associated with Turner syndrome?
- Short stature so consider GH treatment
- CV system (coarctation of aorta, bicuspid aortic deviation, aortic dissection, hypertension)
- Renal congenital abnormalities
- Metabolic syndrome
- Hypothyroidism
- Hearing problems
- Osteoporosis
What is congenital adrenal hyperplasia (CAH)?
A disorder of cortical biosynthesis in the adrenal glands. It causes the release of little cortisol and a lot of male hormones
95% of cases are caused by 21-hydroxylase deficiency
What are the presentations of CAH in childhood?
- Salt wasting (salt wasting and shock)
- Virilisation (ambiguous genitalia in girls and early virilisation in boys)
- Precocious puberty
- Abnormal growth
What is Virilisation?
A development of male physical characteristics in a female or precociously in a boy
What are the presentations of CAH in adulthood?
- Hirsutism
- Oligo/Amenorrhoea
- Acne
- Subfertility
Similar to PCOS presentation
What is the treatment for CAH?
- Glucocorticoid and mineralocorticoid replacement
- Additional salt in infancy
- Surgical management of ambiguous genitalia
