1. Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania;
2. Department of Obstetrics and Gynecology, Hospital of Lithuanian University of Health Sciences Kauno klinikos, Kaunas, Lithuania;
3. Medical Faculty, Vilnius University, Vilnius, Lithuania;
4. Center of Obstetrics and Gynecology, Vilnius University Hospital Santaros Clinic, Vilnius, Lithuania