OBJECTIVES To study interaction of early onset pauciarticular juvenile chronic arthritis (EOP-JCA) and pregnancy in the Polish population, in particular to confirm the ameliorating effect of pregnancy on disease activity reported by others and to analyse the factors that govern the occurrence of postpartum flare, with emphasis on the potential role of breast feeding.

RESULTS 23 women had at least one successful pregnancy, seven had unsuccessful pregnancies but all of them had also one or more successful pregnancies. Among those who have never been pregnant (n=16) there was a higher frequency of eye disease and ExEOP-JCA compared with the rest of the group. In almost all cases pregnancy was associated with remission of disease activity, however a postpartum flare appeared after 22 pregnancies (52%). The flares were more frequent in women who had an active disease before pregnancy, had a flare after a previous pregnancy and/or were breast feeding.

CONCLUSIONS In EOP-JCA patients pregnancy generally has a good outcome and induces amelioration of disease activity. After delivery, however, a flare of disease often appears, especially in women who were breast feeding, had a postparum flare previously or had an active disease before pregnancy. The pattern of interaction between disease and pregnancy found in EOP-JCA makes EOP-JCA similar in this respect to RA, but different from systemic lupus erythematosus and ankylosing spondylitis.