Disease activity during and after pregnancy in women with axial spondyloarthritis: a prospective multicentre study

Objective. The aim was to study disease activity in women with axial spondyloarthritis (axSpA) during and after pregnancy. Methods. The study included 179 pregnancies in 166 women with axSpA from a Norwegian nationwide register. Disease activity was assessed at seven time points before, throughout and after pregnancy with the DAS BASDAI. Scores assessed at each time point were analysed in a linear mixed model. The same statistical method was used to study self-reported physical functioning, pain and mental health. Results. Altogether, disease activity was stable throughout the study period. We found the highest disease activity and worst self-reported pain in the second trimester, when 45% of the women had active disease. At this time point, disease activity was significantly higher than 6 weeks postpartum (mean BASDAI 3.97 vs 3.46, P = 0.005). Self-reported mental health was also stable, but significantly better 6 weeks postpartum than in the first trimester (mean RAND-36 mental health 79.3 vs 73.2, P<0.001). Physical functioning was significantly worse in third trimester than postpartum (mean BASFI 3.6 vs 2.6, P<0.001). Conclusion. Studying women with axSpA, we found that disease activity was highest in the second trimester, but altogether low and stable in the period from planning pregnancy to 1 year after delivery.