Causes of abnormal bleeding

Non-reproductive causes

• Systemic disease disorders of blood coagulation - eg, von Willebrand's disease or prothrombin deficiency, leukaemia, idiopathic thrombocytopenic purpura and hypersplenism. 
• Hypothyroidism - can sometimes be associated with menorrhagia or intermenstrual bleeding (IMB). 
• Cirrhosis - associated with reduced ability of the liver to metabolise oestrogens, and hypoprothrombinaemia.

Diseases of the reproductive tract

• The most common causes during fertile age are those related to pregnancy - eg, threatened, incomplete or missed abortion, ectopic pregnancy. Trophoblastic disease should be considered in women with recent pregnancy.
• Malignancies - endometrial and cervical carcinoma are the most common; also ovarian carcinoma.
• Endometritis - usually presents as intermenstrual spotting.
• Fibroids, endometrial polyps and adenomyosis.
• Cervical lesions - erosions, polyps and cervicitis - can present as postcoital spotting.
• Iatrogenic - hormones used for contraception or hormone replacement therapy (HRT) or management of other conditions. Some psychotropic drugs (eg, risperidone).

Dysfunctional uterine bleeding

Dysfunctional uterine bleeding (DUB) is defined as abnormal uterine bleeding in the absence of organic disease.

• It usually presents as heavy menstrual bleeding (menorrhagia). The diagnosis of DUB can only be made once all other causes of abnormal or heavy, uterine bleeding have been excluded. The pathophysiology is largely unknown.
• The National Institute for Health and Care Excellence (NICE) defines heavy menstrual bleeding as 'excessive menstrual blood loss which interferes with the woman's physical, emotional, social and material quality of life, and which can occur alone or in a combination with other symptoms'.^[1]

Investigations

Ask women to complete a menstrual calendar:

• Note the total duration of bleeding and how much of that time it is heavy. Over 90% of menstrual loss occurs in the first 3 days and there is no correlation with the duration of loss and the total volume.
• Note the length of the cycle, ie the duration from the start of one period to the start of the next.
• Every woman presenting with heavy menstrual bleeding should have an FBC taken. The most common cause of iron-deficiency anaemia in women is menorrhagia.
• Tests for endocrine abnormalities, including TFTs, should be performed only if there is clinical suspicion.
• Assessment of bleeding disorders is only indicated if there is clinical suspicion.
• If appropriate, you should refer the patient for a biopsy to exclude endometrial cancer or atypical hyperplasia. Indications for a biopsy include:
  • Persistent IMB which has not improved with medical management.
  • Age ≥45 years.
  • Women with a history to suggest endometrial pathology.
  • Women with risk factors for endometrial cancer or hyperplasia.
• Luteal phase (day 21) serum progesterone to determine if ovulating.

Management

This depends on the underlying cause. Menstrual disorders are very common in adolescence, and can be the cause of a significant amount of stress both to the patients and to their parents.^[2] 

Pharmacological

In DUB:^[1]

• First-line: levonorgestrel-releasing intrauterine system - provided that long-term use (ie at least 12 months) is anticipated.
• Second-line: tranexamic acid or non-steroidal anti-inflammatory drugs (NSAIDs), if non-hormonal preferred, or combined oral contraceptive pills (COCPs).
• There is some evidence to suggest that COCPs can reduce menstrual blood loss by 40-50%.^[3] 
• Third-line: norethisterone (15 mg tds, from day 5 to 26 or injected long-acting progestogens). This can result in a significant reduction in menstrual blood loss, although women tend to find the treatment less acceptable than intrauterine levonorgestrel. This regimen of progestogen may have a role in the short-term treatment of menorrhagia.
• However, there are very limited data regarding the use of progestogens and of oestrogens and progestogens in combination in the treatment of irregular menstrual bleeding associated with anovulation. There is still no consensus about which regimens are the most effective.^[4] 

Surgical

This should only be considered if:

• Pharmacological management has failed
• There is severe impact on quality of life
• There is no desire to conceive
• The uterus is normal (or there are just small fibroids <3 cm)

Options include endometrial ablation and hysterectomy.

When to refer to secondary care

Referral to secondary care for further gynaecological assessment and examination should be made:

• In women aged over 45 years with heavy menstrual bleeding.
• If there is persistent IMB.
• If an abnormality is suspected on physical examination (other than fibroids <3 cm in diameter).
• If there is suspicion, from the history, of increased risk of pathology, such as carcinoma (eg, family history or endometrial or colonic cancer, nulliparity, obesity, tamoxifen or unopposed oestrogen therapy, abnormal smear, polycystic ovarian syndrome).
• If there is treatment failure.