A question from Yahoo! Answers:

Did the ‘Nazis’ castrate male communists,homosexuals and others?

Not systematically. The primary target of German sterilization policy as mandated by the “racial hygiene” laws were mental patients (by and large German) of both sexes. It is estimated that between 300,000 and 400,000 mental patients (both men and women) were sterilized between 1934 and 1945.

Sterilization of Jews, Gypsies, homosexuals, and people of mixed African and German parentage was not mandated by law, but was sometimes carried out on a limited scale as a local initiative. Dr. Horst Schumann, for example, conducted numerous chemical sterilization experiments on Jewish and Gypsy women imprisoned in Auschwitz and Birkenbau. About 500 Afro-German teenagers (the offspring of French colonial troops stationed in the Rhineland in the early 1920s) were sterilized by secret order in mid-1930s.