Risk of adverse pregnancy outcomes prior to the onset of an autoimmune rheumatic disease: a systematic review

OBJECTIVES: An increased risk of adverse maternal and foetal pregnancy complications (including pre-eclampsia, intrauterine growth restriction, and small for gestational age) is well described in women with autoimmune rheumatic disease (ARD) compared with the general population (GenPop). It is less clear, however, whether this risk of adverse pregnancy outcome (APO) also exists in women with ‘preclinical ARD’ (pre-ARD) before they are diagnosed with an ARD many years post-partum. Therefore, we have undertaken a systematic review of the available evidence on APO in patients who subsequently were diagnosed with a rheumatic disease to identify whether there is an increased risk in pre-ARD. METHODS: The present study was reported in accordance with the guidance of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standard. A systematic literature review was performed using the online PubMed database. Pre-SLE and pre-RA patients were defined as those who, over the subsequent years, developed SLE or RA according to international classification criteria. RESULTS: A total of 176 articles were screened, and 27 original articles were selected for final analysis. Pre-RA was the most studied group, with 15 studies and a total of >1600 pregnancies, and pre-SLE was the second-most studied pre-ARD in pregnancy, with 14 studies and a total of >1000 pregnancies. We found that patients who subsequently developed SLE had an increased burden of poor pregnancy outcomes compared with pregnant women from the GenPop, but fewer APOs compared with pregnancies of women with SLE. In contrast, a similar rate of APOs was found when pre-RA pregnancies were compared with GenPop pregnancies. CONCLUSION: Our findings of an increased risk of APO in certain pre-ARDs highlights the relevance of taking an obstetric history during the first rheumatology appointment and the need for novel screening strategies for the prediction of APOs. Further research is required to elucidate the immune basis of APOs in preclinical and clinical ARD.