What is the recommended treatment for a molar pregnancy?

Treatment of Molar Pregnancy

Suction dilation and curettage (D&C) under ultrasound guidance is the definitive treatment for molar pregnancy in women who wish to preserve fertility. 1, 2

Primary Surgical Management

Suction D&C is the treatment of choice because it provides the safest method to evacuate uterine contents while minimizing the risk of uterine perforation. 2 The procedure should be performed under ultrasound guidance to ensure complete evacuation and reduce complications. 2, 3

Key Technical Points:

• Administer Rho(D) immunoglobulin at the time of evacuation for all Rh-negative patients. 2, 3
• Use uterotonic agents (methylergonovine and/or prostaglandins) during the procedure and continue for several hours postoperatively to reduce bleeding risk. 2, 3
• Avoid medical evacuation methods as they are not recommended for molar pregnancy. 4
• Do not perform biopsy of visible lesions due to high risk of life-threatening hemorrhage. 1

Alternative Surgical Options:

• Hysterectomy is an appropriate alternative for women who have completed childbearing and do not wish to preserve fertility. 2, 3, 4 This approach reduces the risk of malignant sequelae. 5

Post-Evacuation hCG Monitoring Protocol

All patients require strict hCG surveillance to detect the development of gestational trophoblastic neoplasia (GTN). 1, 2

Monitoring Schedule:

• Measure serum hCG every 1-2 weeks until three consecutive normal values are achieved (hCG <1-2 mIU/mL). 1, 2, 3
• For complete hydatidiform mole: Continue monthly hCG monitoring for 6 months after normalization. 1, 6, 2
• For partial hydatidiform mole: One additional normal hCG value is required before discharge from monitoring. 6, 2
• Reliable contraception is mandatory during the entire follow-up period to avoid confusion with pregnancy-related hCG elevation. 1, 2, 4

Diagnostic Criteria for Post-Molar GTN

Post-molar GTN is diagnosed when any of the following FIGO criteria are met: 1, 2

• hCG levels plateau (less than 10% change) for 4 consecutive values over 3 weeks 1, 2
• hCG levels rise >10% for 3 consecutive values over 2 weeks 1, 2
• hCG persistence for 6 months or more after molar evacuation 1, 2

Management of Post-Molar GTN

When GTN is diagnosed, additional staging workup is required including Doppler pelvic ultrasound and chest X-ray. 1, 2 If chest X-ray shows metastatic disease, proceed with brain MRI and CT of chest/abdomen/pelvis. 1

Treatment Based on FIGO Scoring:

Low-risk GTN (FIGO score 0-6):

• Single-agent chemotherapy with methotrexate or dactinomycin is the standard treatment. 1, 4
• Methotrexate is administered at 15-30 mg daily for 5 days, repeated for 3-5 courses with rest periods of 1+ weeks between courses. 7
• Continue chemotherapy for 6 weeks of maintenance after hCG normalization. 1

High-risk GTN (FIGO score ≥7):

• Multi-agent combination chemotherapy is required, with EMA/CO being the most commonly used regimen. 1
• Maintenance therapy should extend for 6-8 weeks after hCG normalization, with longer duration (8 weeks) for poor prognostic features like liver or brain metastases. 1

Role of Repeat Curettage:

Repeat D&C can be considered for persistent postmolar GTN confined to the uterus, but this approach has limitations. 1, 2 In one study of 544 women, 68% had no further disease after second curettage, but chemotherapy was more likely needed when histology confirmed persistent disease or urinary hCG exceeded 1,500 IU/L. 1 This should only be attempted after discussion with a GTD reference center. 1

Prophylactic Chemotherapy Considerations

Prophylactic chemotherapy at evacuation is controversial and not routinely recommended. 2 However, it may be considered for high-risk patients with: 2, 3

• Age >40 years
• hCG levels >100,000 mIU/mL
• Excessive uterine enlargement
• Theca lutein cysts >6 cm

Studies suggest prophylactic methotrexate or dactinomycin reduces postmolar GTN incidence by 3-8%. 3

Critical Pitfalls to Avoid

• Never biopsy visible lesions in the lower genital tract due to hemorrhage risk from fragile vessels. 1
• Do not use preserved methotrexate formulations for high-dose therapy as they contain benzyl alcohol. 7
• Always use the same laboratory for serial hCG measurements to ensure consistency, as different assays have varying sensitivities. 6, 3
• Do not discontinue contraception during follow-up period, as pregnancy will interfere with hCG monitoring. 1, 2, 4

Long-Term Follow-Up

After completing post-molar surveillance, measure hCG 8 weeks after termination of all future pregnancies. 6, 4 Offer early ultrasound (around gestational week 8) in all subsequent pregnancies. 4 The risk of recurrent molar pregnancy is 1-2% in subsequent pregnancies. 8