The results of these studies, however, could have been influenced by the fact that
identification of AFE was based on clinical diagnosis as recorded in the medical record,
without other verifying evidence, and depended on correct coding of that diagnosis.
Moreover, nonfatal AFE might have been over diagnosed in these studies. A prospective,
national study of amniotic fluid embolism using the UK Obstetric Surveillance System
(UKOSS) is currently in the process of assessing whether these risk factors are present in
this population.