Management of Molar Pregnancy
The management of a patient with molar pregnancy requires prompt surgical evacuation by suction dilation and curettage (D&C) under ultrasound guidance, followed by systematic hCG monitoring to detect potential development of gestational trophoblastic neoplasia (GTN). 1
Initial Diagnosis and Assessment
Molar pregnancy is often diagnosed based on ultrasound findings, clinical symptoms, and elevated hCG levels 1
Complete workup should include:
- History and physical examination
- Pelvic ultrasound
- Quantitative hCG assay
- Complete blood count with platelets
- Liver, renal, and thyroid function tests
- Blood type and screen
- Chest X-ray 1
Characteristic ultrasound findings:
Primary Management
- Surgical evacuation is the treatment of choice for molar pregnancy in women who wish to preserve fertility 1
- Suction D&C under ultrasound guidance is the safest method to:
- Ensure adequate emptying of uterine contents
- Avoid uterine perforation 1
- Administer Rho(D) immunoglobulin at evacuation to patients with Rh-negative blood types 1
- Use uterotonic agents (e.g., methylergonovine, prostaglandins) during and after the procedure to reduce risk of heavy bleeding 1
- For women who do not wish to preserve fertility or are older, hysterectomy can be considered as an alternative 1
- Histopathologic review of evacuated tissue is essential to confirm diagnosis 1
Post-Evacuation Monitoring
- All women with molar pregnancy require careful hCG monitoring to detect potential development of GTN 1
- NCCN Guidelines recommend:
- hCG monitoring every 1-2 weeks until levels normalize (defined as 3 consecutive normal assays)
- After normalization, hCG should be measured twice in 3-month intervals 1
- For diploid hydatidiform mole (complete mole):
- If hCG normalizes within 56 days after evacuation, follow-up can be discontinued after an additional four monthly measurements
- If hCG normalizes after 56 days, monthly hCG measurements should continue for 6 months 2
- For triploid partial mole:
- Weekly hCG measurements until two consecutive undetectable values, after which follow-up can be discontinued 2
- Reliable contraception should be used during the entire follow-up period 1, 2
Criteria for Post-Molar GTN
Post-molar GTN is diagnosed when meeting any of the following FIGO criteria:
- hCG levels plateau for 4 consecutive values over 3 weeks
- hCG levels rise >10% for 3 values over 2 weeks
- hCG persistence 6 months or more after molar evacuation 1
Management of Post-Molar GTN
- If GTN is diagnosed, additional staging workup includes:
- Doppler pelvic ultrasound
- Chest X-ray (if positive, proceed with MRI brain and CT body) 1
- Treatment is based on FIGO scoring system that predicts resistance to single-agent chemotherapy:
- Low-risk (score 0-6): Single-agent chemotherapy (methotrexate or actinomycin D)
- High-risk (score ≥7): Multi-agent chemotherapy 1
- Indications for chemotherapy include:
- Plateaued or rising hCG after evacuation
- Heavy vaginal bleeding
- Histological evidence of choriocarcinoma
- Evidence of metastases
- Serum hCG ≥20,000 IU/L >4 weeks after evacuation 1
Special Considerations
- Re-biopsy to confirm malignant change is not advised due to risk of triggering life-threatening hemorrhage 1
- Prophylactic chemotherapy at time of evacuation is controversial and generally not recommended as standard practice, but may be considered for high-risk patients 1
- Risk factors for post-molar GTN include:
- Age >40 years
- hCG levels >100,000 mIU/mL
- Excessive uterine enlargement
- Theca lutein cysts >6 cm 1
- For recurrent molar pregnancies, genetic workup and counseling should be considered 2