Background The effect of pregnancy on spondyloarthropathies such as ankylosing spondylitis (AS) or axial psoriatic arthritis (PsA) is not clear. Some reports claim a beneficial effect during pregnancy  while others mention there is no particular effect or that there might be an aggravation of symptoms [2,3,4].
The methods of measuring disease activity in AS are not yet validated for pregnancy and their applicability in this context is questionable. C-Reactive protein (CRP) and especially erythrocyte sedimentation rate (ESR) are increased during normal pregnancy [5,6] and this might affect disease activity scores and their interpretation. Ankylosing Spondylitis Disease Activity Score (ASDAS) is not yet proven to correlate with disease activity in AS and other spondyloarthropathies with axial involvement.
Objectives To study and characterize a population of women with axial spondyloarthritis before, during pregnancy and post-delivery and to evaluate disease activity indexes in this population.
Methods We prospectively evaluated 30 women, with a mean age of 31.5±4.7 years, 25 with the diagnosis of ankylosing spondylitis and 5 with axial psoriatic arthritis.
AS/PsA patients were considered active if the visual analogue scale (VAS) of nocturnal back pain and fatigue ≥30 plus morning stiffness >30 minutes, and/or ≥1 swollen or tender joint or ≥2 active enthesitis or dactylitis or Psoriasis Area Severity Index (PASI) ≥10 or exacerbation of associated inflammatory bowel disease.
ASDAS-CRP/ESR were calculated. Statistical treatment was performed using SPSS-20.
Results Before conception, disease was active in 3 out of 30 AS/PsA patients, with an overall mean ASDAS-ESR/CRP of 0.49/0.11. During pregnancy there was an increase in disease activity until the 3rd trimester (p=0,005) and after labour (p=0,025). During the 2nd trimester two thirds of all patients had an active disease. Ultrasound-verified hip synovitis was found in nine patients, all symptomatic and requiring prednisolone treatment. Eigth women stopped working due to disease activity.
ASDAS-ESR/CRP was correlated with disease activity (p=0,003, p=0,012, respectively).
Conclusions Disease activity during pregnancy is increased in AS and axial PsA. ASDAS seems like a promising tool for the follow-up of these patients during pregnancy.
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Disclosure of Interest None declared