German gynecologist; born at Höngg, near Zurich, Switzerland, June 30, 1848; educated at the University of Zurich (M.D. 1871). In 1871 he received the "venia legendi" at the University of Strasburg, where he had already become assistant in the gynecological institute. In 1876 he was appointed professor of gynecology at the University of Erlangen, and in 1887 he was transferred to Leipsic. He has the title "Geheimer Medizinal-Rat."

Zweifel has contributed over one hundred monographs to medical journals. Among his many works may be mentioned: "Ueber den Verdauungsapparat der Neugeborenen" (Strasburg, 1874); "Lehrbuch der Operativen Geburtshülfe" (Stuttgart, 1881; appeared as "Lehrbuch der Geburtshülfe," ib. 1887, 5th ed. 1901); "Der Einfluss der Aerztlichen Thätigkeit auf die Bevölkerungsbewegung" (ib. 1887); "Die Symphyseotomie" (ib. 1893); and "Aetiologie, Prophylaxis und Therapie der Rachitis" (ib. 1900).

Bibliography: Pagel, Biog. Lex.;
Meyers Konversations-Lexikon;
Brockhaus Konversations-Lexikon.S. F. T. H.