1. 1. Perinatology Clinic of the Collegium Medicum, Jagiellonian University, Krakow
2. 2. Department of Prenatal Cardiology, Polish Mother’s Memorial Hospital Research Institute, Lodz, Poland
3. 3. Institute of Health Sciences, The State School of Higher Professional Education in Płock, Poland
4. 4. Medical University of Lodz, Department of Diagnoses and Prevention Fetal Malformations