In the classification of abnormal uterine bleeding, which of the following is categorized under the COEIN group (non-structural causes)?

Explanation

## PALM-COEIN Classification of Abnormal Uterine Bleeding (FIGO 2018) **Key Point:** The FIGO classification divides AUB into two broad categories: **PALM** (Structural) and **COEIN** (Non-structural). Understanding this framework is essential for systematic evaluation and management. ### PALM-COEIN Framework | Category | Acronym | Causes | Structural? | |----------|---------|--------|-------------| | **Structural** | **PALM** | **P**olyp, **A**denomyosis, **L**eiomyoma, **M**alignancy | Yes — visible on imaging or histology | | **Non-Structural** | **COEIN** | **C**oagulopathy, **O**vulatory dysfunction, **E**ndometrial, **I**atrogenic, **N**ot yet classified | No — functional or systemic disorder | ### COEIN Subcategories Explained 1. **Coagulopathy** - Inherited: von Willebrand disease (most common), factor XI deficiency, platelet disorders. - Acquired: anticoagulation therapy, thrombocytopenia. - Prevalence: ~13% of women with HMB; up to 20% in adolescents with severe menorrhagia. 2. **Ovulatory Dysfunction** - PCOS, hypothyroidism, hyperprolactinemia, anovulation (immature HPO axis in adolescence). - Most common non-structural cause in reproductive age. 3. **Endometrial** - Endometritis, endometrial atrophy (postmenopausal), endometrial hyperplasia (without atypia). - Functional abnormalities of endometrial hemostasis or angiogenesis. 4. **Iatrogenic** - Hormonal contraceptives (OCPs, progestins, IUDs). - Anticoagulants, antiplatelet agents, antipsychotics (risperidone). 5. **Not Yet Classified** - Emerging entities without established pathophysiology. **High-Yield:** Coagulopathy is the ONLY systemic disorder in the COEIN classification. It must be screened for in adolescents with heavy menstrual bleeding (HMB) or a family history of bleeding disorder, as 5–20% of adolescents with HMB have an underlying coagulopathy. **Mnemonic:** **PALM = Pathology (you can see it)**; **COEIN = Conditions (functional/systemic)**. ### Why Coagulopathy Is Non-Structural Coagulopathy causes AUB through a **functional defect in hemostasis** (deficient clotting factors, platelet dysfunction, or anticoagulation), not through anatomical distortion of the uterus. The endometrium and myometrium appear normal on imaging and histology. **Clinical Pearl:** A woman presenting with heavy menstrual bleeding + personal/family history of easy bruising, epistaxis, or prolonged bleeding after dental work should be evaluated for coagulopathy with PT/INR, aPTT, platelet count, and von Willebrand factor panel before attributing her AUB to structural causes.