1 Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
2 Department of Haematology and Coagulation, Sahlgrenska University Hospital, Gothenburg, Sweden.
3 Perinatal Centre, Department of Obstetrics and Gynaecology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
4 Department of Obstetrics and Gynaecology, Sahlgrenska University Hospital/East, Gothenburg, Sweden.