ABSTRACT
A decisive step towards a scientific understanding of female fertility was the discovery of the menstrual cycle at the beginning of the twentieth century. Following Karl von Baer's discovery of the egg, the connection between ovulation and menstruation received much attention, but misconceptions and prejudices created methodological difficulties. For ordinary people, knowledge of the menstrual cycle could be used to control unwanted pregnancies. Feminists and their conservative Christian opponents approached birth control from opposite ends of the spectrum. There was no difference between abortion and birth control, a point well illustrated by the Catholic Church, which spoke about contraception as just another form of infanticide. In view of developments in embryology, it was easy to brush it aside as a faulty and outdated biological theory. The only technique that could be tolerated was permanent sexual abstinence initiated and signed by a religious vow. Since the Nazis' misuse of his name, Haeckel is strongly associated with anti-Semitism and eugenics.
