Amenorrhoea is defined as the absence of menstruation (regular periods) in women of reproductive age. It can be primary or secondary. It is distinctly different from oligomenorrhoea – which is the presence of irregular periods.
Physiological amenorrhoea occurs during pregnancy and breastfeeding. It is also often seen with many types of hormonal contraception.
Primary Amenorrhoea
This occurs when the patient has never had a period
This should be investigated in:
- 14 year old girls with no breast development
- 15 year old girls
The most common cause is late puberty (which is often familial), and you can reassure parents and patients that this is most likely the case.
When to consider further investigation
- Are the external genitalia normal?
- If so, are the internal genitalia normal?
- Consider genotypic karyotyping for:
- Turner’s Syndrome
- Testicular feminization
True primary amenorrhoea is often caused by either congenital absence or underdevelopment of the ovaries or uterus.
Secondary Amenorrhoea
- Emotional distress
- Weight loss / low body weight – a body fat percentage of <17% is associated with amenorrhoea
- Excessive exercise
- Systemic disease
- Hyperthyroidism
- Drug Induced – commonly by contraceptive agents (particularly progesterone only), anti-psychotics, and women taking long term opiates
Other things to consider
- Early menopause occurs in about 1% of those with secondary amenorrhoea
- Polycystic ovarian syndrome – PCOS
Rare causes include:
- Pituitary tumours
- Pituitary necrosis
- Early menopause occurs in about 1% of patients
Investigations
- FSH – may be very high in premature menopause
- Testosterone – may be raised in polycystic ovarian syndrome
- LH – may be raised in polycystic ovarian syndrome
- TFT’s – amenorrhoea may be due to Hyperthyroidism – also note that hypothyroidism can cause the opposite effect: menorrhagia
Management
This essentially involves treating the underlying cause. In women who do not plan on having any biological children treatment may not be required.
References
- Murtagh’s General Practice. 6th Ed. (2015) John Murtagh, Jill Rosenblatt
- Oxford Handbook of General Practice. 3rd Ed. (2010) Simon, C., Everitt, H., van Drop, F.