title: A prospective clinical study of the effect of pregnancy on rheumatoid arthritis and ankylosing spondylitis.
mesh_terms: D001168:Arthritis / Q000503:physiopathology; D001172:Arthritis, Rheumatoid / Q000503:physiopathology*; D001724:Birth Weight; D002585:Cesarean Section; D005260:Female; D006801:Humans; D049590:Postpartum Period; D011247:Pregnancy; D011248:Pregnancy Complications; D011446:Prospective Studies; D011565:Psoriasis / Q000503:physiopathology; D013167:Spondylitis, Ankylosing / Q000503:physiopathology*