K Å Salvesen1, C Lees, J Abramowicz, C Brezinka, G Ter Haar, K Maršál. 1. National Center for Fetal Medicine, St. Olav University Hospital of Trondheim and Department of Laboratory Medicine, Women's and Child Health, Norwegian University of Science and Technology, N 7006 Trondheim, Norway. pepe.salvesen@ntnu.no