1. Students Scientific Association at the 1st Department of Obstetrics and Gynecology, First Faculty of Medicine, Medical University of Warsaw, 02-091 Warsaw, Poland
2. National Institute of Cardiology, Clinical Research Support Center, 04-628 Warsaw, Poland
3. The Center of Postgraduate Medical Education, Department of Obstetrics, Perinatology and Neonatology, 01-813 Warsaw, Poland