Gynecology Topic 07. Abnormal uterine bleeding / dysfunctional uterine bleeding

I. Definition and Terminology

Definition

• Abnormal uterine bleeding (AUB): uterine bleeding with abnormal quantity, duration, frequency, regularity, or timing.
• Dysfunctional uterine bleeding (DUB): older term for AUB without identifiable structural lesion; usually hormonal/anovulatory.

Normal Menstrual Parameters

• Menstrual cycle: 21-35 days, median about 28 days.
• Duration of bleeding: <8 days.
• Volume of blood loss: <80 mL/cycle.

Bleeding Pattern Terms

• Oligomenorrhea/raromenorrhea: abnormally infrequent bleeding; cycles >35 days.
• Polymenorrhea: abnormally frequent bleeding; cycles <21 days.
• Hypermenorrhea/menorrhagia: increased, heavy or prolonged menstrual bleeding.
• Hypomenorrhea: decreased menstrual bleeding.
• Metrorrhagia: bleeding between periods.
• Menometrorrhagia: heavy and irregular bleeding.

II. Etiology and Pathophysiology

FIGO PALM-COEIN Classification

1. Structural causes: PALM

• Polyp.
• Adenomyosis.
• Leiomyoma, especially submucosal fibroid.
• Malignancy and hyperplasia, especially endometrial cancer/hyperplasia.

2. Non-structural causes: COEIN

• Coagulopathy.
• Ovulatory dysfunction: anovulation/PCOS; most common DUB mechanism.
• Endometrial dysfunction: primary disorder of local endometrial hemostasis.
• Iatrogenic: OCPs, progestins, anticoagulants, copper/progestin IUD.
• Not otherwise classified.

Anovulatory DUB

• Mechanism: no corpus luteum → no cyclic progesterone → unopposed estrogen → endometrial proliferation → unstable overgrown endometrium → irregular profuse shedding.
• Typical groups: adolescents after menarche, perimenopause, PCOS, obesity.
• Other triggers: thyroid disease, hyperprolactinemia, stress, malnutrition/eating disorder.

III. Clinical Features and Diagnosis

Clinical Features

• Bleeding may be too frequent, too infrequent, heavy, prolonged, irregular or intermenstrual.
• Heavy bleeding → clots, flooding, anemia symptoms: fatigue, dizziness, pallor, tachycardia.
• Pain suggests structural/inflammatory disease more than classic DUB.
• Pregnancy-related bleeding must always be excluded.

History and Examination

• History: age, bleeding pattern, pregnancy risk, contraception, drugs/anticoagulants, systemic disease, bleeding tendency.
• Ask for PCOS symptoms, thyroid symptoms, galactorrhea, weight change, stress/eating disorder and family history.
• Physical/pelvic exam: vitals, anemia, genital tract source, cervical/vaginal lesion, infection, uterine enlargement or adnexal mass.

Diagnostic Workup

1. If unstable: IV access, fluids and blood products before full workup.
2. Pregnancy test: beta-hCG in every reproductive-age patient.
3. CBC/ferritin → anemia; platelet count and coagulation profile if heavy bleeding/bleeding tendency.
4. Liver and thyroid function tests; hormones when indicated: FSH, LH, estradiol, PRL, androgens.
5. Pelvic US first-line; MRI only if US is unclear or deep pathology suspected.
6. Pap smear/cervical evaluation and endometrial biopsy if cancer/hyperplasia risk.
7. Saline infusion sonography or hysteroscopy if intracavitary lesion suspected.

When Endometrial Biopsy Is Important

• Age ≥45 years with AUB.
• Younger patient with obesity, PCOS/chronic anovulation, diabetes, prolonged unopposed estrogen or persistent bleeding.
• Suspicious ultrasound/endometrial finding.

IV. Treatment

Initial Management

• Treat anemia: iron supplementation; blood transfusion if severe/unstable.
• Hemodynamic instability or severe ongoing bleeding → urgent gynecologic management and resuscitation.

Medical Treatment of Stable AUB

• Hormonal cycle control: combined oral contraceptives or progestins → suppress endometrial proliferation and create predictable withdrawal bleeding.
• Levonorgestrel IUD: strong option for chronic heavy menstrual bleeding if malignancy is excluded.
• Tranexamic acid: antifibrinolytic → decreases menstrual blood loss.
• NSAIDs: pain relief and modest reduction of menstrual blood loss; avoid if contraindicated.
• Treat underlying cause: thyroid/PRL disorder, coagulopathy, iatrogenic cause, infection, polyp/fibroid or malignancy.

Surgical Treatment

• Hysteroscopy ± polypectomy/myomectomy: intracavitary polyp or submucosal fibroid.
• D&C: diagnostic/temporary therapeutic option in selected severe or persistent bleeding; important in older patients in oral exam notes.
• Endometrial ablation: refractory heavy bleeding after malignancy excluded; fertility is not preserved.
• Hysterectomy: definitive last resort or malignancy/premalignancy indication.