Hilde G1, Stær-Jensen J2, Brækken I H3, Engh M E4, Bø K1
1. Norwegian School of Sports Sciences, Department of Sports Medicine, Oslo, Norway; Akershus University Hospital, Department of Obstetrics and Gynaecology, Lørenskog, Norway, 2. Akershus University Hospital, Department of Obstetrics and Gynaecology, Lørenskog, Norway, 3. Norwegian School of Sports Sciences, Department of Sports Medicine, Oslo, Norway, 4. Akershus University Hospital, Department of Obstetrics and Gynaecology, Lørenskog, Norway; Faculty Division Akershus University Hospital, University of Oslo, Norway