A 28-year-old woman from rural Maharashtra presents with vaginal bleeding and lower abdominal pain for 3 weeks. She had a positive urine pregnancy test 8 weeks ago but denies any fetal movements. On examination, her uterus is larger than expected for gestational age, and there is no fetal heart sound on Doppler. Serum β-hCG is 185,000 mIU/mL. Transvaginal ultrasound shows a heterogeneous intrauterine mass with multiple small cystic spaces and no fetal parts. What is the most likely diagnosis?

Explanation

## Clinical Presentation & Diagnosis **Key Point:** Complete hydatidiform mole (CHM) presents with a uterus disproportionately large for dates, markedly elevated β-hCG (typically >100,000 mIU/mL), and a characteristic 'bunch of grapes' ultrasound appearance with hydropic villi and no fetal tissue. ### Distinguishing Features of Complete vs. Partial Mole | Feature | Complete Mole | Partial Mole | |---------|---------------|---------------| | **Fetal tissue** | Absent | Present (abnormal) | | **β-hCG level** | Very high (>100,000) | Moderate (10,000–100,000) | | **Uterine size** | Large for dates | Appropriate or small | | **Ultrasound** | Homogeneous echogenic mass, no fetus | Fetal tissue + abnormal placenta | | **Karyotype** | 46,XX (90%) or 46,XY (10%) — all paternal | 69,XXY or 69,XXX — diandric | | **Malignant potential** | 15–20% → GTN | 1–5% → GTN | ### Why This Case Is Complete Mole 1. **No fetal parts** on ultrasound — rules out partial mole 2. **Markedly elevated β-hCG** (185,000) — typical of CHM 3. **Uterus large for dates** — due to excessive trophoblastic proliferation 4. **Heterogeneous mass with cystic spaces** — classic 'bunch of grapes' pattern **High-Yield:** Complete moles have a 15–20% risk of persistent gestational trophoblastic neoplasia (GTN) and require post-evacuation monitoring with serial β-hCG for 6–12 months. [cite:Jeffcoate's Principles of Gynaecology Ch 22] **Clinical Pearl:** Invasive mole and choriocarcinoma are diagnoses of GTN (made after evacuation of a mole), not at initial presentation. Choriocarcinoma typically presents with metastatic symptoms (hemoptysis, neurological signs) and occurs weeks to months after molar evacuation or normal pregnancy.