[Sperm stains in legal medicine. An historical review of forensic authentication methods]

Furnishing proof of human seminal stains is part of daily forensic work in investigations of sexual crimes. In the last two centuries different methods have been described for confirming putative sperm traces. These methods ranged from identification of the smell and appearance of the stain, to simple chemical reactions such as precipitation of crystals and enzymatic proof of acid phosphatase, which are now enhanced by analytic methods of modern molecular biology. This discourse gives a review of the development of different forensic methods for detection of sperm traces, illustrated with historical case studies.