1. Department of Obstetrics and Gynaecology, Riga Stradins University, Riga, Latvia
2. Department of Gynaecology, Riga East University Hospital, Riga, Latvia
3. Institute of Public Health, Riga Stradins University, Riga, Latvia
4. Science Division, Riga East University Hospital, Riga, Latvia
5. Institute of Clinical and Preventive Medicine, University of Latvia, Riga, Latvia