The prevalence of pelvic pain in relation to pregnancy or the post-partum period is high. Pelvic pain with or without disability ranges from 14 to 22% during pregnancy and occurs in 7-10% of women post-partum. The cause of pelvic pain has not been fully elucidated. It may be caused by load-related changes at the pelvic joints sometimes combined with joint hypermobility or other biomechanical factors. Predisposing factors such as normal variants and disposition to inflammatory disorders have never been studied. It is, however, known that MR changes in women who have been pregnant can simulate changes observed in patients with axial spondyloarthritis (SpA); thus, it is a major challenge to distinguish between these conditions, as stated in the description of SpA research.

As a part of the current PhD studies by Rosa Marie Østergaard Kiil and Louise Kjeldsen, we intend to evaluate the evolution of MR changes in the pelvic joints during and after pregnancy and relate the changes to clinical symptoms and findings. Additionally, biochemical tests associated with SpA will be performed giving the possibility to detect imaging and clinical features potentially distinguishing pregnancy-related changes from inflammatory changes in SpA.

The analyses are based on prospective examinations of pregnant women during and after pregnancy as well as retrospective analyses og data from the cohort of patients with low back pain collected at the Spine Center of Southern Denmark.

The prospective study is performed in a scientific collaboration with Uppsala University, Sweden, also recruiting participants.

Anne Grethe Jurik, MD, DMSc, Professor, Consultant Radiologist, Department of Radiology, AUH: annejuri@rm.dk

Rosa Marie Østergaard Kiil, MD, PhD student, Department of Radiology, AUH: rosaande@rm.dk

Niels Egund, DMSc, Professor Emeritus, Department of Radiology, AUH: nielegun@rm.dk

Anne Gitte Rasmussen Loft, MD, DMSc, Department of Rheumatology, AUH: Anne.Gitte.Loft@auh.rm.dk

Berit Schiøttz-Christensen, MD, DMSc, Professor, Spine Center of Southern Denmark: Berit.Schiottz-Christensen@rsyd.dk

Flemming Brandt Sørensen, MD, DMSc, Professor, Department of Pathology, AUH: FLSOER@rm.dk

Rikke Damkjær Maimburg, Midwife, PhD, Department of Gynaecology and Obstetrics, AUH: rikkmaim@rm.dk

Per Kristiansson, MD, PhD, Department of Public Health and Caring Sciences, Family Medicine and Preventive Medicine, Uppsala University, Sweden: per.kristiansson@pubcare.uu.se