1. PEDEGO Research Center; University of Oulu and Department of Obstetrics and Gynecology; Oulu University Hospital; Oulu Finland
2. Department of Obstetrics & Gynecology; Rovaniemi Central Hospital; Rovaniemi Finland
3. Department of Clinical Microbiology; Northern Finland Laboratory Center; Oulu Finland
4. PEDEGO Research Center; University of Oulu and Department of Children and Adolescents; Oulu University Hospital; Oulu Finland
5. Tampere Center for Child Health Research; University of Tampere and Tampere University Hospital; Tampere Finland
6. Northern Finland Laboratory Center; Rovaniemi Finland
7. Department of Clinical Chemistry; Northern Finland Laboratory Center; Oulu Finland