Pregnancy outcomes in women with rheumatic diseases: a real-world observational study in Japan

Objectives: We aimed to evaluate the obstetric complications and the risk factors for these events in pregnant women with rheumatic diseases (RDs). Methods: A single-center retrospective study of women with RDs at Hokkaido University Hospital between 2007 and 2016 was conducted. Clinical features and maternal and fetal outcomes were retrospectively collected. The rate of pregnancy complications was compared with the general obstetric population (GOP) in Japan. Results: Overall, 132 pregnancies in 95 women with RDs were recorded. Underlying RDs were systemic erythematosus (SLE) (n = 57), antiphospholipid syndrome (APS) (n = 35), rheumatoid arthritis (n = 9), and other RDs (n = 31). Antiphospholipid antibodies (aPL) were detected in 44 pregnancies (32%). Glucocorticoid was used in 82 pregnancies (62%), and tacrolimus in 20 pregnancies (15%). There were 24 disease flares (18%), but no RD-related death was documented. We recorded 112 live births, 6 abortions, 8 miscarriages, and 6 stillbirths. Pregnancies with RDs appeared to have frequent, emergency cesarean sections and preterm deliveries compared with GOP (30% vs 15% and 21% vs 14%, respectively). The median [interquartile range] birthweight in SLE and APS was lower than GOP (2591 [2231–2958] g and 2600 [2276–2920] g vs 2950 [2650–3250] g, respectively). In pregnancies with SLE, low complement levels presented the risk of maternal complications (odds ratio [95% CI]; 3.9 [1.0–14.9], p = 0.046) and anti-DNA antibody positivity was significantly correlated with the risk of fetal complications (3.5 [1.1–11.2], p = 0.036). In pregnancies with APS, maternal age over 35 years and duration of disease longer than 9 years (7.4 [1.3–40.8], p = 0.021, and 11.16 [1.1–118.8], p = 0.046, respectively) were significantly correlated with the risk of fetal complications. Conclusion: Pregnancies with RDs were at increased risk of having both maternal complications and adverse neonatal outcomes, indicating these pregnancies should be closely monitored.