Risk of Pregnancy Complications and Low Birth Weight Offsprings in Korean Women With Rheumatic Diseases: A Nationwide Population-Based Study

Background: To determine the risk of pregnancy complications and adverse offspring outcomes in Korean women with rheumatic diseases (RDs). Methods: Women aged 20-44 years with pregnancies ending in delivery were identified from the National Health Insurance Service-National Health Information Database (2009-2016). Women with RD including systemic lupus erythematosus (SLE), seropositive rheumatoid arthritis (SPRA), and ankylosing spondylitis (AS) (n = 4,284) were age-matched with controls (n = 26,023). Outcome variables included threatened abortion (TA), preterm birth (PB), preeclampsia/eclampsia (PE/E), intrauterine growth retardation (IGR), urinary tract infection, low birth weight (LBW) offsprings, and offspring death within 1 year of birth. Results: Women with RDs had increased risks for cesarean section delivery (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.4-1.6), TA (OR, 1.4; 95% CI, 1.2-1.5), PB (OR, 2.4; 95% CI, 1.9-3.2), PE/E (OR, 4.4; 95% CI, 3.3-5.9), and IGR (OR, 2.4; 95% CI, 2.0-3.1) than the controls. The risk of pregnancy complications was increased in SLE and SPRA pregnancies but not in AS pregnancies. Offsprings of women with RDs had an increased risk of LBW (OR, 4.0; 95% CI, 3.2-4.9). The offspring mortality rate within 1 year of birth was higher in women with RDs (6.2/10,000 persons) than in the controls (4.9/10,000 persons). Conclusion: Women with RDs are at a risk of developing pregnancy complications, and the risk of LBW offsprings and offspring death within 1 year of birth is increased in these women. Therefore, this population requires special attention during their childbearing years.