Amenorrhoea + Oligomenorrhoea Flashcards
How do you classify Amenorrhoea?
Primary and Secondary
What is Primary Amenorrhoea? (2 things)
Failure to start menses (aka no menarche) in:
- 16+ yr w secondary sexual characteristics (e.g pubic hair / breast dev)
- 14+ yr w NO secondary sexual characteristics
What is Secondary Amenorrhoea?
Periods stop for 6+ months (after menarche obv)
What is Oligomenorrhoea? (2 things)
- Irregular periods w intervals of 35+ days
- +/- Less than 9 periods / year
What are the titles of the causes of Amenorrhoea? (3 things)
- Hypothalamic causes
- Pituitary causes
- Ovarian / Genital causes
How does clartation of the Hypothalamus cause Amenorrhoea? (3 steps)
- Reduced GnRH secretion
- Reduces pulsatile release of LH + FSH from Ant Pit
- Anovulation
What are the Hypothalamic causes of Amenorrhoea? (3 things)
- Anorexia nervosa
- Extreme exercise
- Stress
How does clartation of the Pituitary gland cause Amenorrhoea? (2 steps)
- Reduced release of LH + FSH from Ant Pit
- Anovulation
What are the Pituitary causes of Amenorrhoea? (3 things)
- Prolactinoma
- Pituitary adenoma
- Sheehan’s syndrome
How do Prolactinomas cause Amenorrhoea? (4 steps)
- High levels of prolactin released
- Prolactin inhibits GnRH sec
- Reduces pulsatile release of LH + FSH from Ant Pit
- Anovulation
What is Sheehan’s syndrome?
Post-partum pituitary necrosis (secondary to massive obstetric haemorrhage)
What are the Ovarian / Genital causes of Amenorrhoea? (3 things)
- PCOS
- Ovarian failure
- Ashermann’s syndrome
Does PCOS more commonly cause Amenorrhoea or Oligomenorrhoea?
Oligomenorrhoea
What is Ovarian failure?
Premature ovarian insuffiency (aka menopause before age of 40)
What are the CF of Ovarian failure?
Menopause symptoms like hot / night sweats
What do hormone profile tests show in Ovarian failure? (2 things)
- Low oestrogen
- High FSH
What is Ashermann’s syndrome?
Damage to basal layer of endometrium –> intrauterine adhesions
What causes Ashermann’s syndrome?
Damage to uterus from Surgical management of miscarriage
What are the most common causes of Oligomenorrhoea? (7 things)
- PCOS
- Contraceptive / hormonal tx
- Perimenopause
- Hypo / Hyperthyroidism
- DM
- Eating disorders / excessive exercise
- Medications
How can Hypothyroidism cause Oligomenorrhoea? (4 steps)
- Decreased T3/T4
- TRH upregulated
- Stimulates Prolactin secretion
- LH / FSH inhibited
How can Hyperthyroidism cause Oligomenorrhoea? (4 steps)
- High T3/T4
- Increased Sex Hormone Binding Globulin (SHBG)
- Reduced ratio of free / bound oesteadiol
- LH spike not triggered
What medications can cause Oligomenorrhoea? (2 things)
- Anti-psychotics
- Anti-epileptics
What investigations should you do for Amenorrhoea / Oligomenorrhoea? (5 things)
- Pregnancy test
- Bloods
- Karyotyping
- US
- Progesterone challenge test
What bloods should you do for Amenorrhoea / Oligomenorrhoea? (4 things)
- TFT
- Prolactin
- FSH / LH / Oestradiol / Progesterone / Testosterone
- 17 hydroxyprogesterone (to check for Congenital adrenal hyperplasia)