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 oligmenorrhoea – which is the presence of irregular periods.

Physiological amenorrhoea occurs during pregnancy and breastfeeding. It is also often seen with many types of 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 karotyping for:
    • Turner’s Syndrome
    • Testicular feminization

True primary amenorrhoea is often caused by congenital absence of the ovaries or uterus, or undeveloped ovaries or uterus.

Secondary Amenorrhoea

Common causes – the hypothalamic – pituitary – ovarian axis can be easily unbalanced by many things, including:
  • 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

Rare causes include:

  • Pituitary tumours
  • Pituitary necrosis
  • Early menopause occurs in about 1% of patients

Investigations

Blood Tests
  • 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 Hyperthyroidismalso note that hypothyroidism can cause the opposite effect: menorrhagia

Management

This essentially involves treating the underlying cause. If women who do not plan on having any biological children then treatment may not be required.