What is the treatment for molar pregnancy?

Treatment of Molar Pregnancy

The primary treatment for molar pregnancy is surgical evacuation by suction dilation and curettage (D&C) under ultrasound guidance, regardless of uterine size, in patients who wish to preserve fertility. 1, 2

Initial Management

• Suction D&C under ultrasound control is the safest method to ensure adequate emptying of uterine contents and avoid uterine perforation 1, 3
• Blood should be available pre-operatively due to risk of significant hemorrhage during evacuation 3
• Administer Rho(D) immunoglobulin at evacuation to patients with Rh-negative blood types 1, 3
• Uterotonic agents (e.g., methylergonovine, prostaglandins) should be used during and after the procedure to reduce risk of heavy bleeding 1
• Hysterectomy is an alternative for women who have completed childbearing or are older (>40 years) with higher risk of malignant transformation 4

Post-Evacuation Monitoring

• All women with molar pregnancy require careful hCG monitoring to detect potential development of gestational trophoblastic neoplasia (GTN) 1, 3
• hCG monitoring should be done every 1-2 weeks until levels normalize (defined as 3 consecutive normal assays) 1, 5
• After normalization, for complete hydatidiform mole, monthly hCG monitoring for 6 months is recommended 3
• For partial hydatidiform mole, one additional normal hCG measurement one month after initial normalization is sufficient 3, 6
• Reliable contraception should be used during the entire follow-up period 1, 7

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 5, 1
• hCG levels rise >10% for 3 values over 2 weeks 5, 1
• hCG persistence 6 months or more after molar evacuation 5, 1
• Histological evidence of choriocarcinoma 5
• Evidence of metastases in the brain, liver, gastrointestinal tract, or radiological opacities of >2 cm on chest X-ray 5
• Serum hCG of ≥20,000 IU/L >4 weeks after evacuation, due to risk of uterine perforation 5

Management of Post-Molar GTN

• If GTN is diagnosed, additional staging workup includes Doppler pelvic ultrasound and chest X-ray 1
• If chest X-ray is positive, proceed with MRI brain and CT body for complete staging 1, 5
• Repeat D&C can be considered for persistent postmolar GTN; studies show 68% of patients may not require further treatment after second evacuation 5
• Treatment is based on FIGO scoring system: low-risk (score 0-6) is treated with single-agent chemotherapy (methotrexate or actinomycin D) 1, 4
• High-risk GTN (score ≥7) requires multi-agent chemotherapy 1, 8

Special Considerations

• Re-biopsy to confirm malignant change is not advised due to risk of triggering life-threatening hemorrhage 3
• Prophylactic chemotherapy at time of evacuation is controversial but may be considered for high-risk patients who may have unreliable follow-up 2, 8
• Risk factors for post-molar GTN include age >40 years, hCG levels >100,000 mIU/mL, excessive uterine enlargement, and theca lutein cysts >6 cm 1, 5
• Twin pregnancies with a coexistent normal twin and complete hydatidiform mole can result in healthy babies in approximately 40% of cases 3

Pitfalls and Caveats

• Medical evacuation (misoprostol) should not be used for molar pregnancy due to increased risk of GTN and hemorrhage 6
• Endometrial ablation is contraindicated in patients with a history of molar pregnancy due to risk of undetected recurrent GTN 3
• Patients with recurrent complete hydatidiform mole may have familial recurrent hydatidiform mole (FRHM), requiring genetic counseling 3, 6
• In all future pregnancies after molar pregnancy, early ultrasound (around 8 weeks) is recommended to confirm normal development 6
• hCG measurement 8 weeks after termination of all future pregnancies is recommended to rule out recurrent disease 6