Accurate amniotic fluid bilirubin analysis from the "bloody tap". A preliminary report.

The quantitation of bilirubin in amniotic fluid is of paramount importance in prognosticating the severity of Rh isoimmunization. Amniotic fluid contaminated by maternal blood can result in erroneous results when direct spectrophotemetric analysis is performed on such fluid. The technique and results of a one-step chloroform extraction performed on "bloody" amniotic fluid is presented. Results confirm that chloroform extraction yields more accurate clinical information in regard to Rh isoimmunized patients in whom a "bloody tap" is obtained.