1. Diatheva s.r.l., Sant’Anna di Cartoceto (PU), Italy
2. Department of Obstetrics and Gynaecology, Hospital Principe di Piemonte, Senigallia (AN), Italy
3. Center for the prevention and treatment of infections during pregnancy, National Institute for Infectious Diseases (INMI) ‘Lazzaro Spallanzani’, Rome, Italy