Evaluation of abnormal uterine bleeding
Abnormal uterine bleeding is any deviation from normal menstrual volume, duration, frequency, or regularity, classified by the PALM-COEIN system into structural and nonstructural causes. Pregnancy is excluded first with beta-hCG, postmenopausal bleeding gets an endometrial biopsy, and acute heavy bleeding is treated first-line with high-dose IV conjugated estrogen.
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What this article covers
- Overview
A symptom, not a disease: abnormal uterine bleeding (AUB) is any deviation from normal menstruation in volume, duration, frequency, or regularity, or bleeding between periods; normal menses lasts 2 to 7 days.
- Epidemiology
One of the most frequent reasons for gynecologic consultation, spanning adolescence through menopause, with cause distribution shifting by age: anovulation and coagulopathy predominate in…
- Risk factors
Chronic anovulation states: polycystic ovary syndrome and other anovulation causes predispose to irregular bleeding and, after 1-2 years of unopposed estrogen, to endometrial hyperplasia and cancer.
- Pathophysiology
Structural lesions distort the endometrial surface or cavity: polyps and submucosal leiomyomas increase bleeding surface area and disrupt hemostasis at the endometrial-myometrial interface…
- Clinical features
Characterize the bleeding pattern first: cycle length, flow duration, pad/tampon use, and clot passage; the pattern narrows the PALM-COEIN category before any test is ordered.
- Differential diagnosis
Pregnancy-related bleeding (most urgent to exclude): ectopic pregnancy, threatened abortion, or gestational trophoblastic disease; distinguished by a positive beta-hCG, checked before any other cause is pursued.
- Diagnosis
AUB has no single diagnostic criterion; the diagnosis is the specific PALM-COEIN cause, established by excluding pregnancy, then working through labs, structural imaging, and endometrial sampling as indicated by age and risk factors.
- Management
If the patient has acute heavy bleeding causing hemodynamic instability, resuscitate first: IV access, crystalloid, and transfusion as needed for significant anemia or hypotension, while giving IV estrogen in parallel per the next step.
- Complications
Iron deficiency anemia from chronic blood loss, the most common complication of AUB and an indication to treat urgently.
- Prognosis
Prognosis tracks the underlying PALM-COEIN cause, not the bleeding symptom itself: most structural and hormonal causes are well controlled with targeted therapy.
- Prevention
Screen with endometrial biopsy at defined thresholds: endometrial stripe =4 mm in a postmenopausal woman, any postmenopausal bleeding, age 45 years with AUB, or age 35 years with obesity, diabetes, or chronic anovulation.
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Related articles
- Uterine fibroids
Uterine leiomyomas are benign monoclonal smooth-muscle tumors of the myometrium that cause heavy menstrual bleeding, bulk symptoms, and reproductive dysfunction; management ranges from expectant care to hormonal bleeding control to fertility-sparing or definitive surgery.
- Endometrial polyp
Endometrial polyps are focal, usually benign, estrogen-sensitive overgrowths of endometrial glands and stroma projecting into the uterine cavity that present with abnormal or intermenstrual bleeding; diagnosis is by saline-infusion sonohysterography or hysteroscopy, and treatment is hysteroscopic polypectomy with pathology, which is both diagnostic and curative.
- Adenomyosis
Adenomyosis is the presence of endometrial glands and stroma within the myometrium, producing a diffusely enlarged, boggy, symmetric uterus with heavy menstrual bleeding and severe dysmenorrhea; it is a pathologic diagnosis, supported clinically by exam and ultrasound or MRI, and definitively treated with hysterectomy.
- Endometrial cancer
Endometrial cancer is the most common gynecologic malignancy, most often a type I endometrioid adenocarcinoma driven by unopposed estrogen and heralded by postmenopausal bleeding. Any postmenopausal bleeding or thickened endometrial stripe prompts endometrial biopsy, and early-stage disease is treated with total hysterectomy and bilateral salpingo-oophorectomy, giving a favorable overall prognosis.
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Polycystic ovary syndrome (PCOS) is a hyperandrogenic disorder of chronic anovulation and is the most common cause of hirsutism and anovulatory infertility in women. First-line treatment is weight loss for patients with an elevated BMI, combined oral contraceptives for menstrual dysfunction and hirsutism when fertility is not desired, and clomiphene citrate or letrozole for ovulation induction when fertility is desired.
- Von Willebrand disease
Von Willebrand disease is the most common inherited bleeding disorder, caused by deficient or dysfunctional von Willebrand factor, producing mucocutaneous bleeding from impaired platelet adhesion plus a mild secondary factor VIII deficiency. Diagnosis rests on the vWF antigen, ristocetin cofactor activity, and factor VIII activity panel, and management centers on desmopressin for type 1, vWF concentrate for severe or desmopressin-unresponsive disease, and antifibrinolytics for mucosal bleeding.
- Hypothyroidism
Hypothyroidism is thyroid hormone deficiency, most commonly caused by autoimmune (Hashimoto) thyroid failure in iodine-sufficient countries, diagnosed by an elevated thyroid-stimulating hormone with a low or normal free thyroxine. First-line treatment is levothyroxine dosed at 1.6 mcg/kg lean body weight orally once daily, titrated using thyroid-stimulating hormone rechecked no sooner than 6 weeks after any dose change.
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A fertilized ovum implants outside the endometrial cavity, almost always in the fallopian tube, and is the leading cause of maternal death in the first trimester. Diagnosis rests on quantitative beta-hCG paired with transvaginal ultrasound, and management branches immediately on hemodynamic stability.
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