Authors
A. Nikolov
Division of Medicine, Cardiovascular Research Working Group, Institute for Scientific Research, Medical University – Pleven, Bulgaria
N. Popovski
Clinic of Obstetrics and Gynaecology, University Hospital Pleven, Department of Obstetrics and Gynaecology, Medical University – Pleven, Bulgaria
I. Hristova
Department of Midwifery, Faculty of Health Care, Medical University – Pleven, Bulgaria
