Adverse pregnancy outcome and connective tissue disease: why is there a link?

It has been known for many years that there are risks associated with pregnancy for women with a range of established connective tissue diseases (CTD), especially systemic lupus erythematosus (SLE). These risks can be to do with the disease itself, the autoantibodies found in association with the disease, or the medications used to treat symptoms. This recent large, epidemiological study from the UK looks closely at this issue from a different perspective (BJOG 2020 xxxx). Using a retrospective case-control design, the authors examine the risks for women who experienced an adverse pregnancy outcome (APO) of being diagnosed subsequently with a CTD or found to have the antibodies associated with the anti-phospholipid syndrome (APS).