Heavy Menstrual Bleeding: NICE Guideline NG88 Summary

Definition & Key Features

What is Heavy Menstrual Bleeding (HMB)? Heavy menstrual bleeding is defined as excessive menstrual blood loss which interferes with a woman’s physical, emotional, social, and material quality of life. The primary aim of intervention is to improve quality of life, rather than focusing solely on measured blood loss.

Pathophysiology: The underlying cause can be ovulatory dysfunction or structural abnormalities within the uterus. Key structural causes include:
- Uterine fibroids (especially submucosal)
- Adenomyosis
- Endometrial polyps
- Endometrial hyperplasia or carcinoma
- Systemic causes such as coagulation disorders (e.g., von Willebrand’s disease) are less common but important to consider.
Hallmark Features:
- Heavy menstrual bleeding, which may be cyclical or irregular.
- Related symptoms suggesting underlying pathology:
  - Persistent intermenstrual bleeding
  - Postcoital bleeding
  - Pelvic pain (cyclical or non-cyclical)
  - Pressure symptoms (e.g., urinary frequency, constipation)
Complications if Untreated:
- Iron-deficiency anaemia and associated symptoms (fatigue, breathlessness, dizziness).
- Significant negative impact on social, professional, and personal life.

Epidemiology & Risk Factors

Who is most affected? HMB is a common condition affecting women of reproductive age.

Risk Factors for Underlying Pathology: While HMB can occur without any identifiable cause, certain factors increase the risk of significant underlying pathology:
- Coagulation Disorders: Consider in women who have had HMB since menarche and have a personal or family history of bleeding disorders.
- Endometrial Cancer/Hyperplasia: Risk factors include:
  - Persistent intermenstrual or irregular bleeding.
  - Infrequent heavy bleeding in the context of obesity or polycystic ovary syndrome (PCOS).
  - Use of tamoxifen.
  - Failure of previous pharmacological treatments for HMB.

Clinical Presentation & Diagnosis

History Taking:
- Clarify the nature of the bleeding (duration, volume, regularity).
- Elicit related symptoms: persistent intermenstrual bleeding, pelvic pain, pressure symptoms.
- Assess the impact on quality of life.
- Note comorbidities and previous HMB treatments.
Physical Examination:
- Offer an examination if: the woman reports related symptoms (pain, pressure, intermenstrual bleeding) to assess for uterine enlargement or pelvic masses.
- Mandatory before: any imaging, hysteroscopy, or fitting a levonorgestrel-releasing intrauterine system (LNG-IUS).
- May be omitted if: HMB occurs without other symptoms and a pharmacological treatment (other than LNG-IUS) is being initiated.
Red Flags (Indications for Urgent Referral):
- If examination or history suggests malignancy, refer via the 2-week-wait pathway for suspected cancer.
Diagnostic Criteria: The diagnosis is based on the woman’s subjective assessment of heavy blood loss impacting her quality of life.
Differential Diagnoses:
- Fibroids, adenomyosis, endometrial polyps, endometrial pathology (hyperplasia/cancer), coagulation disorders, endometriosis (as a cause of associated pain).
Investigations:
- Laboratory Tests:
  - Full Blood Count (FBC): Perform for ALL women with HMB to check for anaemia.
  - Coagulation Screen: Consider only if HMB has been present since menarche OR there is a personal/family history of a coagulation disorder.
  - DO NOT routinely perform: Serum ferritin, female hormone testing, or thyroid hormone testing (unless other signs/symptoms of thyroid disease are present).
- Imaging & Procedures:
  - Start Pharmacological Treatment First? Consider starting treatment without investigation if history and examination suggest a low risk of fibroids, cavity abnormality, or endometrial pathology.
  - Pelvic Ultrasound (Abdominal or Transvaginal): Offer if:
    - Uterus is palpable abdominally.
    - History or examination suggests a pelvic mass.
    - Examination is inconclusive (e.g., due to obesity).
  - Transvaginal Ultrasound (TVUS): First-line investigation for suspected adenomyosis if the woman presents with significant dysmenorrhoea or has a bulky, tender uterus.
  - Outpatient Hysteroscopy: Offer as the first-line investigation if history suggests submucosal fibroids, polyps, or endometrial pathology (e.g., persistent intermenstrual bleeding or risk factors for endometrial pathology).
    - Advise oral analgesia beforehand.
    - Use vaginoscopy with miniature hysteroscopes (≤3.5 mm).
  - Endometrial Biopsy:
    - Perform only during hysteroscopy for women at high risk of endometrial pathology (see risk factors above).
    - DO NOT perform ‘blind’ endometrial biopsy.
  - DO NOT use as first-line diagnostic tools: Saline infusion sonography, MRI, or dilatation and curettage (D&C).

Initial Management

This approach applies to women with no identified pathology, fibroids <3 cm in diameter (not distorting the uterine cavity), or suspected/diagnosed adenomyosis.

First-Line Treatment:
- Drug: Levonorgestrel-releasing intrauterine system (LNG-IUS).
- Indications: The primary, first-line treatment for HMB in this group.
- Patient Education: Explain that an altered bleeding pattern (irregular bleeding, spotting) is common, especially in the first few cycles and may last longer than 6 months. Advise waiting at least 6 cycles to assess the full benefit.
- Cautions: Requires a physical examination before fitting. Off-label use for some LNG-IUS brands.
Second-Line Treatments (If LNG-IUS is declined or unsuitable):
- Non-Hormonal:
  - Tranexamic Acid:
    - Dosage/Route: 1g orally three times a day for up to 4 days during heavy bleeding.
    - Side Effects: Nausea, vomiting, diarrhoea, dyspepsia.
    - Cautions: Risk of thromboembolism (use with caution if other risk factors are present).
  - Non-Steroidal Anti-inflammatory Drugs (NSAIDs):
    - Dosage/Route (e.g., Mefenamic Acid): 500mg orally three times a day from the start of menses until cessation of heavy flow.
    - Side Effects: Dyspepsia, gastrointestinal irritation/bleeding.
    - Contraindications: History of peptic ulcer disease, renal impairment, NSAID-exacerbated asthma. Note: Off-label use for HMB.
- Hormonal:
  - Combined Hormonal Contraception (CHC): Standard cyclical or continuous regimens. Note: Off-label use for some preparations.
  - Cyclical Oral Progestogens:
    - Dosage/Route (e.g., Norethisterone): 5mg orally two to three times a day from day 5 to day 26 of the menstrual cycle.
    - Side Effects: Weight gain, bloating, breast tenderness, mood changes. Less effective than other options and may not reduce blood loss in ovulatory women.
Monitoring: Review after 3 months for pharmacological treatments (except LNG-IUS) to assess efficacy and side effects. For LNG-IUS, review after 6 months.

Further Management & Escalation

Referral Criteria:
- HMB with fibroids ≥3 cm in diameter.
- Initial management in primary care is unsuccessful, not tolerated, or contraindicated.
- Symptoms are severe.
- Investigations (e.g., ultrasound) show significant structural abnormalities requiring specialist intervention.
- Suspicion of cancer (urgent 2-week-wait referral).
Management of Fibroids ≥3 cm:
- While awaiting specialist assessment, offer tranexamic acid and/or NSAIDs for symptomatic relief.
- Specialist options include:
  - Pharmacological: LNG-IUS, ulipristal acetate (with strict liver function monitoring), GnRH analogues (typically pre-operatively).
  - Uterine Artery Embolisation (UAE): A radiological procedure to block the blood supply to the fibroids.
  - Myomectomy: Surgical removal of fibroids.
Surgical Options (Specialist Care):
- Second-Generation Endometrial Ablation: Destroys the endometrium. Considered for women who have completed their family. Crucially, effective contraception is required post-procedure as pregnancy is dangerous.
- Hysteroscopic Removal of Fibroids/Polyps: For submucosal fibroids or polyps identified on hysteroscopy.
- Hysterectomy: Surgical removal of the uterus. This is a definitive treatment considered when other options have failed or are unsuitable. A full discussion of the implications (fertility, bladder function, psychological impact) is mandatory.
DO NOT offer Dilatation and Curettage (D&C) as a treatment for HMB.

Follow-up & Safety Netting

Frequency of Follow-up:
- Depends on the treatment initiated. Typically 3 months for oral medications, 6 months for LNG-IUS.
- Review as needed based on symptom control and patient preference.
Monitoring Requirements:
- Assess improvement in quality of life and bleeding.
- Check for resolution of anaemia with a repeat FBC if it was initially diagnosed.
- Monitor for side effects of any treatment.
Patient Advice & Self-Management:
- Provide clear information on all treatment options, including benefits and risks.
- For LNG-IUS, manage expectations regarding initial irregular bleeding.
- For endometrial ablation, stress the absolute need for ongoing, effective contraception.
- For hysterectomy, ensure the woman understands the permanent loss of fertility and other surgical implications.
Warning Signs Prompting Urgent Reassessment:
- Sudden worsening of bleeding or pain.
- Development of new, persistent intermenstrual or postcoital bleeding.
- Signs and symptoms of severe anaemia (e.g., syncope, chest pain).
- Signs of liver injury if taking ulipristal acetate (jaundice, nausea, fatigue).

Key Points to Remember

Focus on Quality of Life: The primary goal is to improve the woman’s quality of life, not just achieve a specific reduction in blood loss.
FBC for ALL: Every woman presenting with HMB needs a full blood count. Do not routinely check hormones, ferritin, or thyroid function.
The 3 cm Fibroid Rule: Fibroids <3 cm can often be managed in primary care with an LNG-IUS. Fibroids ≥3 cm warrant specialist referral for discussion of further options.
LNG-IUS is First-Line: For HMB without large fibroids or suspected cancer, the LNG-IUS is the recommended first-line treatment. Counsel patients to persevere for at least 6 months.
No Blind Biopsies or D&C: Endometrial sampling must be done under direct hysteroscopic vision. D&C is not a diagnostic or therapeutic tool for HMB.
Investigate Based on Symptoms: Use ultrasound for palpable masses or suspected adenomyosis. Use hysteroscopy for suspected intracavity pathology (polyps, submucosal fibroids, or persistent intermenstrual bleeding).
Refer When Indicated: Refer if first-line treatment fails, fibroids are large (≥3 cm), or malignancy is suspected (urgent referral).
Contraception After Ablation is CRITICAL: Endometrial ablation is not a method of sterilisation. Subsequent pregnancy is dangerous and must be prevented with effective contraception.
Tranexamic Acid and NSAIDs are Key Second-Line Agents: These are effective, non-hormonal options if an LNG-IUS is declined or unsuitable.

This MedDigest summary is intended for educational purposes only and should not be used for clinical purposes. It is an independent resource, prepared by MedDigest, to offer an accessible overview of information drawn from the NICE guidelines. While MedDigest strives for accuracy in its educational summaries, this content has not been reviewed or produced by NICE. For comprehensive and definitive recommendations, please always refer to the complete NICE guidelines.

References

NICE (24 May 2021) Heavy menstrual bleeding: assessment and management. https://www.nice.org.uk/guidance/ng88