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.