How do you manage a patient with abnormal uterine bleeding (AUB) in family medicine, using the Classification system such as PALM (Polyp, Adenomyosis, Leiomyoma, Malignancy) - COEIN (Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, Not yet classified)?

Management of Abnormal Uterine Bleeding Using the PALM-COEIN Classification System

Abnormal uterine bleeding (AUB) should be systematically evaluated and managed using the PALM-COEIN classification system, which provides a structured approach to identify both structural and non-structural causes and guide appropriate treatment. 1

Initial Assessment

History

• Bleeding pattern characterization:
  • Frequency (frequent, normal, infrequent)
  • Regularity (regular, irregular)
  • Duration (prolonged, normal, shortened)
  • Volume (heavy, normal, light)
• Associated symptoms (pain, dyspareunia, pressure)
• Risk factors for endometrial cancer:
  • Age >45 years
  • Obesity
  • Diabetes
  • Hypertension
  • PCOS
  • Family history of endometrial/colon/breast cancer
  • Tamoxifen use
  • Unopposed estrogen exposure

Physical Examination

• Vital signs (assess for hemodynamic instability)
• BMI calculation
• Pelvic examination to identify:
  • Vaginal/cervical lesions
  • Uterine size/contour
  • Adnexal masses
  • Signs of hyperandrogenism

Laboratory Evaluation

• Pregnancy test (β-hCG)
• Complete blood count
• TSH and prolactin levels
• Coagulation studies if heavy bleeding or suspicion of coagulopathy
• Consider hormonal profile if PCOS or ovulatory dysfunction suspected

Diagnostic Workup Based on PALM-COEIN

Imaging

• Transvaginal ultrasound (TVUS): First-line imaging for all patients with AUB 1

  • Evaluates endometrial thickness
  • Identifies structural abnormalities (polyps, fibroids, adenomyosis)
  • Limitations: body habitus, uterine position, presence of leiomyomas

• Saline infusion sonohysterography (SIS):

  • High sensitivity (96-100%) for intracavitary lesions 1
  • Indicated when TVUS is inconclusive or intracavitary lesions suspected

• MRI:

  • When TVUS is inconclusive
  • Better visualization of adenomyosis
  • Differentiation between leiomyomas and adenomyosis
  • Add diffusion-weighted imaging to improve sensitivity 1

Tissue Sampling

• Endometrial biopsy:

  • Indicated for all women >45 years with AUB
  • Women <45 years with risk factors for endometrial cancer
  • Preferred over D&C (less invasive, safer, lower cost) 1

• Hysteroscopy:

  • Direct visualization of endometrial cavity
  • Diagnosis of focal lesions possibly missed by endometrial sampling
  • Allows for directed biopsies and treatment of polyps/submucosal fibroids

Management Algorithm Based on PALM-COEIN Classification

Structural Causes (PALM)

Polyps (P)

• Hysteroscopic polypectomy
• Follow-up to ensure resolution of symptoms

Adenomyosis (A)

• Medical management:
  • LNG-IUD (88.7% effective in reducing bleeding) 2
  • Combined hormonal contraceptives
  • NSAIDs for pain
• Surgical options if medical management fails:
  • Endometrial ablation (if no future fertility desired)
  • Hysterectomy (definitive treatment)

Leiomyoma (L)

• Medical management:
  • LNG-IUD (less effective at 55.6% compared to other causes) 2
  • Tranexamic acid
  • NSAIDs
  • GnRH agonists (short-term use)
• Surgical options:
  • Hysteroscopic myomectomy for submucosal fibroids
  • Abdominal/laparoscopic myomectomy for intramural/subserosal fibroids
  • Uterine artery embolization
  • Hysterectomy (definitive treatment)

Malignancy and Hyperplasia (M)

• Endometrial hyperplasia without atypia:
  • LNG-IUD (95.5% effective) 2
  • Cyclic progestins
• Atypical hyperplasia or malignancy:
  • Referral to gynecologic oncology
  • Hysterectomy typically required

Non-Structural Causes (COEIN)

Coagulopathy (C)

• Tranexamic acid
• Hormonal therapy (COCs, LNG-IUD)
• Hematology referral if severe
• DDAVP for von Willebrand disease

Ovulatory Dysfunction (O)

• Combined hormonal contraceptives (first-line)
• Progestin-only options (oral, injectable, LNG-IUD)
• Address underlying causes (PCOS, thyroid disease, hyperprolactinemia)
• Weight management if obesity-related

Endometrial (E)

• NSAIDs
• Tranexamic acid
• Hormonal options (COCs, LNG-IUD)
• Endometrial ablation if medical management fails

Iatrogenic (I)

• Modify/discontinue causative medications if possible
• Hormonal treatments to counteract medication effects
• Consider alternative contraceptive methods if IUD-related

Not Yet Classified (N)

• LNG-IUD (92.3% effective) 2
• Symptomatic management based on bleeding pattern
• Re-evaluate diagnosis if treatment fails

Common Pitfalls and Caveats

1. Incomplete evaluation: Only 16.7% of AUB cases are diagnosed according to complete PALM-COEIN criteria 3. Ensure systematic evaluation of all potential causes.

2. Missing endometrial cancer: Always perform endometrial biopsy in women >45 years or those with risk factors regardless of imaging findings.

3. Inadequate imaging: TVUS may miss focal lesions; consider SIS or hysteroscopy when clinical suspicion remains despite normal TVUS.

4. Treatment selection: LNG-IUD effectiveness varies by underlying pathology (less effective for leiomyomas at 55.6% vs. 88-95% for other causes) 2.

5. Overlooking non-structural causes: Laboratory evaluation for coagulopathies, thyroid dysfunction, and ovulatory disorders is essential even when structural abnormalities are identified.

6. Failure to address quality of life: Consider impact of bleeding on anemia, fatigue, and daily activities when determining treatment urgency and aggressiveness.