1Department of Obsteterics and Gynecology, Kuopio University Hospital, University of Kuopio, P.O.B. 1777, 70211 Kuopio, Finland
2Department of Clinical Chemistry, Kuopio University Hospital, University of Kuopio, Kuopio, Finland
3Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, University of Kuopio, Kuopio, Finland