1. Unit of Obstetrics and Gynecology, Department of Clinical Sciences L. Sacco, and Center for Fetal Research Giorgio Pardi, University of Milan, Milan, Italy
2. Dental Clinic, Department of Medicine, Surgery and Dentistry, University of Milano and WHO Collaborating Centre of Milan for Epidemiology and Community Dentistry, Milano, Italy
3. Preventive and Community Dentistry, Department of Oral Sciences, University of Rome “La Sapienza”, Roma, Italy