What is the management of a molar pregnancy?

Management of Molar Pregnancy

The primary treatment for molar pregnancy is suction dilation and curettage (D&C) under ultrasound guidance, followed by rigorous hCG monitoring to detect persistent gestational trophoblastic neoplasia. 1, 2

Initial Diagnosis and Workup

• Minimal requirements:

  • Pelvic ultrasound (shows "snowstorm" appearance in complete molar pregnancy)
  • Quantitative hCG assay (typically elevated)
  • Complete blood count with platelets
  • Liver, renal, and thyroid function tests
  • Blood type and screen
  • Chest X-ray 2

• Additional imaging may be needed if:

  • hCG >100,000 mIU/mL
  • Suspicion of metastatic disease
  • Excessive uterine enlargement 2

Evacuation Procedure

• Suction D&C under ultrasound guidance is the preferred method regardless of uterine size in patients who desire to preserve fertility 2, 3

  • Ultrasound guidance reduces risk of uterine perforation
  • Administer uterotonic agents (methylergonovine and/or prostaglandins) during and after procedure to reduce bleeding risk 2
  • Administer Rho(D) immunoglobulin to Rh-negative patients 2

• Hysterectomy can be considered for:

  • Women who do not wish to preserve fertility
  • Older patients (>40 years)
  • Cases with uncontrolled hemorrhage 2, 4

Post-Evacuation Management

• hCG monitoring:

  • Every 1-2 weeks until levels normalize (defined as 3 consecutive normal assays)
  • After normalization, monitor twice at 3-month intervals 2
  • If normalized within 56 days, continue with 4 additional monthly measurements
  • If normalized after 56 days, continue monthly measurements for 6 months 1

• Reliable contraception is mandatory during the entire monitoring period 1

• Criteria for postmolar GTN diagnosis (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 2

Management of High-Risk Cases

• High-risk features for postmolar GTN:

  • Age >40 years
  • hCG levels >100,000 mIU/mL
  • Excessive uterine enlargement
  • Theca lutein cysts >6 cm 2

• Prophylactic chemotherapy can be considered for high-risk cases:

  • May reduce risk of postmolar GTN by 3-8%
  • Use methotrexate or dactinomycin
  • Not routinely recommended for all cases 2

Management of Persistent Disease (Postmolar GTN)

1. Assessment and staging:

   • History and physical examination
   • Doppler pelvic ultrasound
   • Chest X-ray (if normal, no further imaging needed before treatment)
   • FIGO scoring system to determine risk 2

2. Treatment options:

   • Repeat D&C may be considered for persistent GTN, especially when hCG <1,500 IU/L 2
   • Low-risk disease (FIGO score ≤6): Single-agent chemotherapy with methotrexate/folinic acid or actinomycin D 2
   • High-risk disease (FIGO score ≥7): Multi-agent chemotherapy (EMA/CO regimen) 2

Special Considerations

• Twin pregnancy with molar component:

  • If fetus appears normal, 40-60% chance of healthy baby
  • Higher risk of pre-eclampsia and other complications
  • Should be managed in high-risk obstetric units 2

• Avoid biopsy of visible lesions in lower genital tract due to hemorrhage risk 1

• False-positive hCG results:

  • Consider phantom hCG if elevated with no evidence of disease on imaging
  • Urine hCG can help confirm suspected false-positive serum results 1

Prognosis and Follow-up

• With proper management and follow-up, cure rates approach 100% 1
• Fertility is generally preserved, with 83% of women becoming pregnant after chemotherapy 2
• No significant increase in congenital malformations in subsequent pregnancies 2
• When a patient becomes pregnant, confirm normality by ultrasound and discontinue hCG monitoring, but recheck hCG at 6 and 10 weeks after pregnancy 2

The management of molar pregnancy requires a systematic approach with careful monitoring to ensure complete resolution and early detection of persistent disease. Centralization of care, pathology review, and adherence to hCG monitoring protocols are essential for optimal outcomes 2.