1. Department of Obstetrics, Women’s Diseases and Oncogynecology, National Institute of Medicine of the Ministry of Interior and Administration, Woloska 137, 02-507 Warsaw, Poland
2. Department of Obstetrics and Gynecology, Institute of Mother and Child, Kasprzaka 17a, 01-211 Warsaw, Poland
3. Chair of Epidemiology and Preventive Medicine, Department of Epidemiology, Jagiellonian University Medical College, 7 Kopernika St., 31034 Krakow, Poland
4. Center for Reproductive Health, Institute of Mother and Child, Kasprzaka 17a, 01-211 Warsaw, Poland