1. Department for Women's Health University Hospital of Tübingen Tübingen Germany
2. Laboratory Prof. Gisela Enders and Colleagues Stuttgart Germany
3. Department of Obstetrics and Prenatal Medicine University Hospital of Bonn Bonn Germany
4. Department of Obstetrics and Gynaecology University Hospital of Cologne Cologne Germany
5. Department of Obstetrics and Gynaecology University Hospital of Erlangen Erlangen Germany
6. Institute for Medical Virology and Epidemiology of Viral Diseases University of Tübingen Tübingen Germany