lev-os Managing Abnormal Uterine Bleeding
Guides AUB evaluation using the FIGO PALM-COEIN classification system, age-stratified workup algorithms, and evidence-based management per ACOG Practice Bulletin No. 128.
Why This Skill Exists
Abnormal uterine bleeding (AUB) affects approximately one-third of women over their lifetime and is the most common reason for gynecologic office visits and a leading indication for hysterectomy. The International Federation of Gynecology and Obstetrics (FIGO) introduced the PALM-COEIN classification system (2011, revised 2018) to standardize the terminology and categorize AUB by etiology rather than by the legacy terms "dysfunctional uterine bleeding" or "menorrhagia" alone. ACOG Practice Bulletin No. 128 provides the diagnostic workup framework.
Failure to evaluate AUB systematically risks missing endometrial cancer (especially in postmenopausal women or those with risk factors), uterine fibroids requiring intervention, or coagulation disorders. This skill structures the evaluation to ensure no etiology is overlooked.
Checkpoint A: Pre-Draft Intake (Mandatory)
- Patient age and menopausal status — reproductive age, perimenopause, or postmenopausal? (Default: from demographics)
- Bleeding pattern — heavy menstrual bleeding (HMB), intermenstrual bleeding (IMB), prolonged bleeding, irregular cycles, postmenopausal bleeding? (Default: from history)
- Bleeding severity — estimated blood loss, pad/tampon count, passing clots, symptoms of anemia? (Default: use pictorial blood loss assessment chart if available)
- LMP and pregnancy test — always exclude pregnancy first in reproductive-age women. (Default: order urine or serum βhCG)
- Medications — anticoagulants, hormonal contraception, HRT, tamoxifen? (Default: from medication list)
- Medical history — coagulation disorders, thyroid disease, PCOS, liver disease, renal disease? (Default: from problem list)
- Family history — bleeding disorders, endometrial cancer, colon cancer (Lynch syndrome)? (Default: from family history)
- Prior workup — imaging, biopsies, lab results already obtained? (Default: from chart review)
Documents to Request
- Menstrual calendar or bleeding diary
- Prior pelvic ultrasound reports (transvaginal preferred)
- Endometrial biopsy pathology reports
- CBC with platelet count, ferritin
- TSH
- Coagulation studies (if indicated)
- Pap smear and HPV results
- Hysteroscopy reports (if performed)
- Saline infusion sonohysterogram (SIS) reports
Step 1: Apply the FIGO PALM-COEIN Classification
Every case of AUB should be categorized by etiology:
PALM — Structural Causes (assessed by imaging/pathology)
| Category | Description | Key Diagnostic Method |
|---|---|---|
| P — Polyp | Endometrial or endocervical polyps | Transvaginal US, SIS, hysteroscopy |
| A — Adenomyosis | Endometrial tissue within myometrium | MRI (gold standard), TVUS (globular uterus, heterogeneous myometrium) |
| L — Leiomyoma | Submucosal (SM), intramural (IM), subserosal (SS) — use FIGO fibroid subclassification 0–8 | TVUS, SIS, MRI |
| M — Malignancy/hyperplasia | Endometrial hyperplasia or carcinoma, cervical cancer | Endometrial biopsy, hysteroscopy with biopsy |
COEIN — Non-Structural Causes (clinical/laboratory diagnosis)
| Category | Description | Evaluation |
|---|---|---|
| C — Coagulopathy | Von Willebrand disease, platelet disorders, anticoagulant use | CBC, PT/INR, aPTT, VWF panel, factor levels |
| O — Ovulatory dysfunction | PCOS, hypothalamic amenorrhea, thyroid disease, hyperprolactinemia | TSH, prolactin, androgens, progesterone day 21 |
| E — Endometrial | Primary disorder of endometrial hemostasis (diagnosis of exclusion) | After other causes excluded |
| I — Iatrogenic | IUD-related bleeding, anticoagulants, hormonal medications | Medication review |
| N — Not yet classified | Rare causes (AVM, cesarean scar defect) | Specialized imaging |
Document the PALM-COEIN category using the notation: AUB-P, AUB-L (SM), AUB-O, etc.
Step 2: Age-Stratified Workup Algorithm
Reproductive Age (< 40 years) with AUB
- Pregnancy test (mandatory first step)
- CBC, ferritin (assess for iron deficiency anemia)
- TSH
- Transvaginal ultrasound
- Coagulation screening if: HMB since menarche, family history, bleeding with dental/surgical procedures (screen for von Willebrand disease)
- Endometrial biopsy if: age ≥ 35 with risk factors, failed medical management, persistent AUB
Perimenopause (40+ years) with AUB
- Pregnancy test
- CBC, ferritin, TSH
- Transvaginal ultrasound
- Endometrial biopsy — indicated for all women ≥ 45 with AUB, or ≥ 40 with risk factors (obesity, PCOS, tamoxifen, unopposed estrogen, Lynch syndrome)
- SIS or hysteroscopy if ultrasound suggests intracavitary pathology
Postmenopausal Bleeding
- Any bleeding after 12 months of amenorrhea must be evaluated for endometrial cancer
- Transvaginal ultrasound: endometrial thickness ≤ 4 mm has 99% negative predictive value for cancer
- Endometrial thickness > 4 mm or persistent bleeding → endometrial biopsy
- SIS or hysteroscopy if biopsy is non-diagnostic or insufficient
Step 3: Fibroid Sub-Classification (FIGO)
When leiomyoma is identified, classify by location:
| FIGO Type | Location | Clinical Impact |
|---|---|---|
| 0 | Pedunculated intracavitary | Highest AUB impact — hysteroscopic resection |
| 1 | Submucosal, < 50% intramural | High AUB impact — hysteroscopic resection |
| 2 | Submucosal, ≥ 50% intramural | Moderate AUB impact — may require combined approach |
| 3 | 100% intramural, contacts endometrium | Moderate impact — assess cavity distortion |
| 4 | Intramural, no endometrial contact | Lower AUB impact — medical management first |
| 5 | Subserosal, ≥ 50% intramural | Unlikely AUB cause |
| 6 | Subserosal, < 50% intramural | Unlikely AUB cause |
| 7 | Pedunculated subserosal | Not typically AUB cause |
| 8 | Other (cervical, parasitic) | Rare — specialized management |
Step 4: Medical and Surgical Management
Medical Management Options
| Agent | Mechanism | Typical Use |
|---|---|---|
| LNG-IUD (Mirena) | Endometrial suppression | First-line for HMB — 90% reduction in blood loss |
| Combined OCs | Endometrial stabilization, cycle regulation | AUB-O, AUB-E |
| Tranexamic acid | Antifibrinolytic | 1300 mg TID during menses for HMB |
| NSAIDs (ibuprofen, mefenamic acid) | Prostaglandin inhibition | 20–40% reduction in blood loss |
| GnRH agonists (leuprolide) | Medical menopause | Short-term use pre-surgery or bridge to menopause |
| GnRH antagonist (elagolix, relugolix) | Oral ovarian suppression | FDA-approved for fibroid-related HMB with add-back therapy |
| Progestins (MPA, norethindrone) | Endometrial stabilization | AUB-O, AUB-E, endometrial hyperplasia without atypia |
Surgical Options
- Hysteroscopic polypectomy — for AUB-P
- Hysteroscopic myomectomy — for FIGO types 0, 1, 2
- Abdominal/laparoscopic myomectomy — for large or numerous fibroids with desire for fertility
- Endometrial ablation — for completed childbearing, normal cavity, benign pathology
- Uterine artery embolization — for symptomatic fibroids in non-surgical candidates
- Hysterectomy — definitive treatment for completed childbearing and failed medical management
Checkpoint B: Post-Draft Alignment (Mandatory)
- Is pregnancy excluded as the first step in all reproductive-age patients?
- Is the PALM-COEIN classification assigned with supporting diagnostic evidence?
- Is endometrial biopsy addressed — performed, indicated, or documented as not indicated with rationale?
- Does the management plan match the etiology — medical for AUB-O, surgical for AUB-P/L (SM)?
- Is anemia assessed and managed — ferritin documented, iron replacement initiated if indicated?
Quality Audit
- Pregnancy test documented as performed (reproductive-age patients)
- Bleeding pattern described using FIGO terminology (HMB, IMB, prolonged, irregular)
- PALM-COEIN classification assigned
- CBC and ferritin documented
- TSH documented
- Transvaginal ultrasound performed or ordered
- Endometrial biopsy performed or documented as not indicated (with rationale)
- Fibroid subtype classified by FIGO system (if fibroids present)
- Coagulation screening addressed (performed if indicated, or documented as not indicated)
- Management plan documented with specific agent/procedure and timeline
- Iron replacement documented if ferritin low
- Endometrial cancer risk factors assessed (obesity, PCOS, tamoxifen, unopposed estrogen, Lynch)
- Follow-up plan documented with expected timeframe for treatment response
- Surgical options discussed if medical management fails
Guidelines
- Always exclude pregnancy first — a positive βhCG completely changes the differential and management.
- Use PALM-COEIN, not legacy terms — "dysfunctional uterine bleeding" and "menorrhagia" are imprecise. Use the FIGO classification system in all documentation.
- Biopsy the endometrium liberally — any postmenopausal bleeding, any woman ≥ 45 with AUB, and any woman ≥ 35 with risk factors must have endometrial sampling.
- Classify fibroids by FIGO type — management depends on location (submucosal vs. intramural vs. subserosal), not just size.
- LNG-IUD is first-line for HMB — superior to oral medications for blood loss reduction and patient satisfaction.
- Screen for coagulopathy in young women — von Willebrand disease is present in up to 13% of women with HMB; screen if onset at menarche or positive family history.
- Document failure of medical management before proceeding to surgery — most payers require documentation of medical trial.
- Assess for Lynch syndrome — in patients with endometrial cancer under age 50, or family history of endometrial/colon cancer, refer for genetic counseling.