Hey Kat - you're so right - Probably why its just in testing for RA (the Self article mentions that some autoimmune can worsen during pregnancy, lupus for example, but of course no mention of Ankylosing Spondylitis or Seroneg. Spondylitis at all in the article). I just wonder for those of us who notice a relationship if it would help to have hormones tested. I felt so much better during my pregnancies but I didn't get full blown all-over arthritis til after I weaned my 3rd and last child. I had localized problems before and between pregnancies. I may be grasping at straws.
Mary Cay