Factors associated with time to pregnancy in women with axial spondyloarthritis: A registry-based multicenter study

Abstract

Objective To study time to pregnancy (TTP) and factors associated with TTP in women with axial spondyloarthritis (axSpA), compared to women with rheumatoid arthritis (RA).

Methods We included 274 women with axSpA and 317 women with RA from the Norwegian nationwide registry RevNatus. For all the women, we had retrospectively collected data on TTP, and a subgroup also had prospectively collected data. We compared TTP in women with axSpA to women with RA using Kaplan‐Meier plots and log‐rank test. To identify factors associated with TTP, we used Cox proportional hazard regression.

Results TTP exceeded 12 months in 21% of women with axSpA. In the subgroup followed prospectively, 32% had TTP which exceeded 12 months. Longer TTP was associated with older age, nulliparity, and longer disease duration, with hazard ratios of 0.97 (95% CI 0.94 to 1.00), 0.66 (95% CI 0.50 to 0.88), and 0.94 (95% CI 0.91 to 0.98) respectively. Disease activity, medication, and self‐reported health‐related quality of life were not associated with TTP. We found no statistically significant differences between axSpA and RA in regard to TTP.

Conclusion In women with axSpA, longer TTP was associated with older age, nulliparity, and longer disease duration.