Fetal pericardial effusion

Fetal pericardial effusions (FPE) occur when there is an accumulation of pericardial fluid in utero. In order to be considered as abnormal, it is generally accepted that the pericardial fluid thickness should be greater than 2 mm.

The estimated incidence is at ~ 2% of pregnancies 8.

A fetal pericardial effusion is typically seen as anechoic fluid component greater than 2 mm surrounding the heart (similar to adults). There is no colour flow with Doppler interrogation (c.f. congential cardiac diverticulum 6). If the volume is relatively small, it may present as a lenticular or ovoid collection whereas larger pericardial effusion may give a heart beating in a "bag of water" type appearance.

A careful search for other associations (inclusive of features of hydrops) is recommended.

In the absence of other sonographic abnormalities, an isolated fetal pericardial fluid collection up to 7 mm in thickness is not thought to be associated with an adverse outcome 1.

For a small atypical effusion consider

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Article information

rID: 13431
Tag: cases
Synonyms or Alternate Spellings:
  • Antenetal pericardial effusion
  • In utero pericardial effusion
  • In-utero pericardial effusion
  • Fetal pericardial effusions

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