1. PEDEGO Research Unit (Research Unit for Pediatrics, Dermatology, Clinical Genetics, Obstetrics and Gynecology), University of Oulu, Oulu, Finland
2. Medical Research Center Oulu (MRC Oulu), University of Oulu, Oulu, Finland
3. Department of Obstetrics and Gynecology, Oulu University Hospital, Oulu, Finland
4. Infrastructure for Population Studies, Faculty of Medicine, University of Oulu, Oulu, Finland
5. Finnish Institute of Occupational Health, Oulu, Finland
6. Department of Obstetrics and Gynecology, University of Helsinki, Helsinki University Hospital, Helsinki, Finland
7. Center for Life Course Health Research, Faculty of Medicine, University of Oulu, Oulu, Finland