Identification of fetal blood stains by radioimmunoassay of alpha 1-fetoprotein.

Radioimmunoassay of alpha 1-fetoprotein(AFP) for medico-legal identification of fetal blood stains using a commercial kit is described. The AFP content in fetal blood stains on filter paper ranged from 21--320 ng/9 mm2. The protein was detected in stains of adult blood and retroplacental blood in only negligible amounts. Aging of the blood stains did not influence the values up to 1 month. The method is simple and sensitive enough for application to medico-legal-practice.