Prevention & care

Abnormal menstrual bleeding: patterns, heavy periods, testing and treatment choices

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Abnormal uterine bleeding describes changes in bleeding from the womb: how much, how long, how often or how predictably it happens. It describes a symptom pattern, not its cause. Pregnancy-related bleeding needs a different assessment.[1]

Describe the pattern before naming a cause

Heavy bleeding, prolonged bleeding, irregular cycles and bleeding between periods are different descriptions. FIGO separates those symptom descriptions from its classification of possible causes. Several causes can coexist; a label such as heavy menstrual bleeding does not establish fibroids or a hormone disorder.[2]

Daily life matters more than a perfect volume measurement

Needing frequent product changes, using two products together, leaking onto clothes or bedding, passing large clots, or avoiding ordinary activities can help describe heavy periods. Tiredness or breathlessness may prompt assessment for anemia. Tell the clinician what bleeding interrupts, rather than waiting until you can measure milliliters.[3]

Sudden heavy bleeding needs a severity assessment

Seek emergency care for bleeding with faintness, chest pain or breathing difficulty. ACOG gives changing a pad or tampon hourly for over two hours with these symptoms as an example requiring emergency attention; it is not a rule for waiting until that amount is reached.[1]

Acute heavy uterine bleeding can threaten circulation. Clinical assessment first checks blood loss and stability; controlling the episode and preventing recurrence are separate goals. The acute-care guideline concerns nonpregnant people of reproductive age, not bleeding in pregnancy or after delivery.[4]

Pregnancy possibility and menopause change the pathway

A missed period with unusual bleeding and abdominal or pelvic pain needs urgent assessment for a possible ectopic pregnancy. Bleeding between periods or after sex should be checked, even when contraception seems a plausible explanation. The source can be the cervix or vagina as well as the womb.[5]

Bleeding after menopause warrants assessment even once or in a small amount. The menopause and endometrial-cancer guides explain that pathway.[6]

Separate structural findings from other mechanisms

FIGO groups polyps, adenomyosis, fibroids and lining overgrowth or malignancy as structural categories. Other categories include clotting disorders, ovulation disturbance, lining-related dysfunction and treatment-related bleeding. A scan finding can coexist with another explanation, so discovering a fibroid does not finish the whole assessment.[2]

Choose investigations from the history

NICE recommends a full blood count for heavy menstrual bleeding. Bleeding since periods began plus a personal or family bleeding history may prompt clotting-disorder testing. Routine female hormone testing is not recommended for heavy bleeding; thyroid tests are directed by other suggestive symptoms. History and examination guide ultrasound or hysteroscopy rather than everyone receiving the same test.[7]

Heavy bleeding from the first periods can be informative

ACOG adolescent guidance includes assessment for anemia, including ferritin, ovulation-related endocrine causes and bleeding disorders. Suspected clotting problems may need gynecology and hematology working together. Heavy bleeding in adolescence should not automatically be dismissed as an immature cycle, and a severe acute episode still requires assessment of circulation.[8]

Discuss bleeding control, contraception and fertility together

NICE places preferences, accompanying pain, other conditions and findings at the center of treatment choice. Options may include a levonorgestrel-releasing intrauterine system, other hormonal treatment, tranexamic acid or anti-inflammatory medicines. Suitability and contraindications differ. Ask whether an option is contraceptive, how it affects future pregnancy, and when response will be reviewed.[7]

A short record can make the consultation more useful

Record bleeding days, spotting between periods, product changes, pain and effects on work or sleep. Bring details of contraception, hormonal medicines and other medicines. This helps describe the pattern and possible treatment-related causes; a diary does not need to delay seeking help for concerning bleeding.[1]

Evidence & uncertainty

Treatment evidence concerns particular causes, devices and outcomes. A 2020 review found that a hormone-releasing intrauterine system may improve heavy bleeding and quality of life compared with other medicines, but certainty varied and comparisons with surgery remained less clear.[10]

Selected-source overview · Independent review pending

Published questions

Are heavy periods and irregular periods the same problem?

Selected-source overview · Independent review pending. Read the evidence context.

No. Amount, duration, frequency and predictability describe different aspects of bleeding. Either pattern can have several causes, and more than one pattern may occur together.[2]

Evidence behind this answer

The two FIGO systems for normal and abnormal uterine bleeding symptoms and classification of causes: 2018 revisions
classification consensus · 2018
Relevant original source text read; no independent full evidence appraisal · Sections 3–4: symptom terminology versus PALM-COEIN causes; coexistence