Pre-pregnancy gene expression signatures are associated with subsequent improvement/worsening of rheumatoid arthritis during pregnancy.

"Declarations Ethics approval and consent to participateThe study was approved by the Ethics Committee for Region Hovedstaden (Denmark), the Danish Data Protection Agency, the Children’s Hospital Oakland Research Institute Institutional Review Board (IRB number: 2009–073), and the Northwestern University IRB (IRB number: STU00217093). All subjects provided written informed consent prior to enrollment. Consent for publicationNot applicable. Competing interestsThe authors declare no competing interests. Competing interests The authors declare no competing interests."

"Funding This work was supported by funds from the National Institutes of Arthritis, Musculoskeletal and Skin Diseases (NIAMS), USA (Grants R21AR057931 and R01AR073111); Gigtforeningen, Denmark (grant R87-A1477-B512); and The Juliane Marie Center, Rigshospitalet (Denmark). These funders did not have any role in conducting this study or in the interpretation and reporting of the results."