Determination of Both Fetus' and Mother's Blood Type from an Autopsy Case Immersed in Formalin for Over 50 Years.

A female fetus which had been immersed in formalin for more than 50 years was found in Japan. Because no liquid blood could be obtained, we tried to use immunohistochemistry (IHC) methods to tissue samples obtained at autopsy to identify both the fetal and mother's blood type. We detected B antigens on endothelial cells in paraffin sections of the fetal organs.