Hydatidiform Mole


Developmental anomaly of the trophoblast or placenta in which there is a local or general vesicular change in the chorionic villi.


  • Not very common in UK/Europe (0.05-0.1%) but much moreso in south-east Asia (1 in 500 – 1 in 150)
  • They are more common at extremes of childbearing age, and the risk increases if a previous history of a hydatidiform mole is present.

Clinical Features

  • Amenorrhea; vaginal bleeding; larger than dates uterus; ‘doughy‘ uterus; hyperemesis; pre-eclampsia; failed miscarriage (mole appears like ‘frogspawn’)
  • Patients may have features of thyrotoxicosis since β-hCG seems to partly imitate thyroxine


  • β-hCG (urine and serume)- usually extremely high (>100,000 IU/l)
  • USS- may show classical ‘snowstorm’ appearance in the uterus.  Ovaries may also have theca-lutein cysts.
  • CXR- to check for spread (see below)


  • Evacuation of the uterus
  • Prolonged follow up of urinary/serum β-hCG to check all tissue has been removed (β-hCG should return to normal within 6 months- see below for management should this not occur)
  • Contraception to avoid pregnancy for 1 year (again to ensure the patient is clear of the tumour) if still planning for children; if not, hysterectomy is preferred.


This is the malignant form of a hydatidiform mole and is highly malignant.  Suspicions should be raised if β-hCG levels do not fall following treatment for a mole; if there are symptoms of a mole + symptoms of metastatic spread e.g. haemoptysis, pleuritic chest pain; or evidence on CXR.

Note they may present late after miscarriage/pregnancy/mole as well.

Choriocarcinoma is treated in tertiary centres (subspecialist referral required) and usually responds well to chemotherapy based on methotrexate.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: