Hydatidiform Mole

Hydatidiform Mole is a topic covered in the 5-Minute Emergency Consult.

To view the entire topic, please or purchase a subscription.

Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:

Emergency Central

-- The first section of this topic is shown below --



  • Noninvasive localized tumors arising from trophoblastic tissue
  • Can be associated with malignancy
  • Twinning with normal pregnancy possible:
    • Higher risk for persistent maternal disease and metastasis
    • Possible to have normal infant
  • Complete mole:
    • Estimated in 1/1,500 pregnancies
    • Fetal tissue not present
    • Diffuse chorionic villi swelling
    • Diffuse trophoblastic hyperplasia
    • Malignancy associated in 15–20%, usually lung
    • Genetics:
      • Karyotype: 46, XX (90%); 46, XY (10%)
      • Paternal DNA expressed
      • Enucleate egg fertilized by 2 sperms or by a haploid sperm that duplicates
  • Partial mole:
    • Estimated in 1/750 pregnancies
    • Fetal or embryonic tissue often present
    • Focal chorionic villi swelling
    • Focal trophoblastic hyperplasia
    • Malignancy associated in 4–12%
    • Genetics:
      • Karyotype: 90% are triploid 69XXX, 69XXY, rarely 69XYY
      • Maternal and paternal DNA
      • Haploid ovum duplicates and is fertilized by normal sperm, or haploid ovum fertilized by 2 sperms


  • Largely unknown
  • Extremes of maternal age best estimated risk factor:
    • >35 yr old carries 5–10-fold risk
    • <20 yr old
  • Previous molar pregnancy carries 1–2% risk in future pregnancies
  • Frequency multiple times greater in Asian and Latin American countries:
    • 1 per 1,000–1,500 live births in US and Western Europe
    • Reported up to 1 per 12–500 live births in other countries
  • Deficiency in animal fat and vitamin A
  • Smoking (>15 cigs/day)
  • Maternal blood type AB, A, or B
  • History of infertility, nulliparity
  • Finding in 1 of 600 therapeutic abortions

-- To view the remaining sections of this topic, please or purchase a subscription --