Menorrhagia describes abnormally heavy bleeding (often associated with increased period pain) during periods.

It is a common presenting compliant, and a cause is not always found. Endometrial carcinoma would always be considered as a differential.

In a typical period, the average blood loss is 30-40ml. Bleeding usually lasts 7 days or less, and a ‘normal’ cycle length is 21-35 days. Up to 30% of women report having “heavy” periods, however only about 5% of women will consult their GP for the problem.

Menstrual disorders are the second most common reason for gynaecology referral.


  • 30% of women report heavy periods
    • When measuring menstrual loss, and using a cut-off of 80mls per menses, the prevalence of menorrhagia is between 10-15%
  • About 50% of cases then present medically have no cause identified – and as such are diagnosed as Dysfunctional Uterine Bleeding (DUB) – a diagnosis of exclusion

Causes of heavy menstrual bleeding

  • Ovulatory Dysfunctional Uterine Bleeding (DUB)
    • Anovulatory DUB – is more rare and occurs at the extremes of child-bearing age
  • Fibroids
  • Complications of hormonal therapy
  • Adenomyosis
  • Endometriosis
  • PCOS
  • Rare, but serious
    • Pregnancy, including its complications (e.g. miscarriage, abortion, ectopic)
    • Cancer – cervical, endometrial, ovarian, leukaemia
    • Endometrial polyps / endometrial hyperplasia
    • PID / STI
  • Other rare things
    • Pelvic congestion syndrome
    • SLE
    • Thyroid disorders
    • Bleeding disorders
    • Liver disease
  • Drugs
  • There is an association with anxiety and depression and heavy menstrual bleeding – which is probably more likely related to a perceptual problem
  • SMOKING – 5x more likely to have abnormal menstruation

Red Flags

  • Heavy bleeding with haemodynamic instability (an emergency!)
  • Postmenopausal
  • During pregnancy
  • Pelvic mass
  • Findings on USS
    • Endometrium >12mm thick in pre-menopausal women
    • Endometrium >5mm thick in peri-menopausal women


  • Menarche
    • Have periods always been heavy? (consider bleeding disorder)
  • Menstrual history
    • What is the normal pattern?
    • When did the heavy bleeding start?
    • What sanitary products does she use and how often are they changed?
    • Note there is no direct correlation between length of period and total blood loss
  • Could she be pregnant?
  • Cervical screening history
  • Effect of symptoms on every day life
    • Is she having regular time off work?
  • Any hirsutism (PCOS signs or symptoms)
  • Sexual history
  • Trauma
  • PMHx
    • Bleeding disorder
    • Thyroid disorder
  • FHx
  • Cancer
  • Hormonal therapy – e.g. contraceptive pill, IUD


Defining heavy bleed can be difficult. A “normal” cycle has bleeding that lasts 7 days or less, with a cycle length of between 21 and 35 days.

Consider that heavy bleeding is present if:

  • >80ml per cycle (hard to determine!)
  • If tampons / pads / cups need to be changed around every hour
  • Having to use two sanitary products in combination
  • Passing large clots. Clots often cause pain as they pass through the cervix
  • If bleeding lasts >1 week


  • If very heavy and acute bleeding – ensure haemodynaically stable
    • HR
    • BP
  • Abdominal / pelvic examination
    • Feel for masses – particularly pelvic masses
  • Consider speculum examination +/- pap smear +/- swabs for STI if indicated
    • Consider if appropriate in young girls with no sexual history as can be a traumatic experience


  • Bloods
    • FBC
    • Iron studies
    • Coags – INR / PT / APTT / fibrinogen / platelets
    • B-hCG
    • TFTs
    • Autoantibodies – e.g. ANA for SLE
    • Consider hormones  – LH, FSH, estradiol, prolactin
  • Consider pelvic / transvaginal USS
    • Ideally should be reserved for women who fail conservative management, or are at high risk of endometrial cancer
    • Perform in first half of cycle when endometrial thickness can be measured
      • >12mm in premenopausal or >5mmin post menopausal women requires endometrial biopsy



  • If haemodynamically unstable – refer to emergency department
  • If haemodynamically stable but Hb <80 – refer for urgent gynaecology assessment (also consider going via emergency)
  • To stop acute bleeding, choose one of the following
    • Tranexamic acid 1g to 1.5g PO every 8 hours – until bleeding ceased
    • Progesterones:
      • Norethisterone 5-10mg PO every 4 hours until bleeding stops
      • Medroxyprogesterone 10mg PO every 4 hours until bleeding stops
  • Consider urgent USS


  • Consider prompt USS
  • Treat any iron deficiency
  • If USS is normal, age <35 and no red flags, can treat in the community. Choose one of the following options:
    • Intra-uterine device (e.g. Mirena)
      • Recommended first line in the UK
      • Studies show women reported a greater improvement in quality of life with mirena compared to other treatments
      • However – has a high rate of removal – about 30% by 2 years
    • Combined hormonal contraceptive (provided no contra-indications). May choose to run packets together to avoid periods altogether – this is safe to do for up to 12 months at a time
    • Tranexamic acid 500mg PO BD or TDS for 2-3 days with periods
    • NSAIDs
      • Ibuprofen 400mg TDS
      • Naproxen 500mg stat dose, and then 250mg TDS
      • Mefanamic acid 500mg TDS
    • Progestins are considered third line, after IUS, CHC / NSAIDs / tranexamic acid
      • Norethisterone – note this is not contraceptive. Start at 5mg TDS. Usually short term use (1-2 months only)
      • Depo-provera injection
        • Suppresses ovulation
        • Beware of reduced bone density and weight gain
        • Repeat every 12 week
    • Endometrial ablation
    • Hysterectomy may be considered as a last resort in women who are certain they do not want any (more) children
  • If no cause is identified, no red flags, and patient is aged <35, and symptoms respond to treatment – you can make a diagnosis of dysfunctional uterine bleeding (DUB)
  • If any red flags, or USS abnormalities, or age >35, refer to gynaecology. USS abnormalities include:
    • Thickened endometrium
      • >12mm in pre-menopausal women
      • >5mm in pro-menopausal women
    • Fibroids – especially if >10cm
    • Endometrial polyps



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