The impact of hydroxychloroquine treatment on pregnancy outcome in women with antiphospholipid antibodies

Background Antiphospholipid syndrome is defined by the combination of thrombotic events and/or obstetric morbidity in patients who have tested positive persistently for antiphospholipid antibodies. With good treatment, approximately 70% of pregnant women with antiphospholipid syndrome will deliver a viable live infant. However, current management does not prevent all maternal, fetal, and neonatal complications of antiphospholipid syndrome. Objectives This observational, retrospective, single-center cohort study aimed to assess pregnancy outcome in women with antiphospholipid antibodies who were treated with hydroxychloroquine in addition to conventional treatment during pregnancy. Study Design One-hundred seventy pregnancies in 96 women with persistent antiphospholipid antibodies were analyzed: (1) 51 pregnancies that occurred in 31 women were treated with hydroxychloroquine for at least 6 months before pregnancy, and the therapy continued throughout gestation (group A); (2) 119 pregnancies that occurred in 65 women with antiphospholipid antibodies that were not treated with hydroxychloroquine were included as controls (group B). Results Hydroxychloroquine-treatment was associated with a higher rate of live births (67% group A vs 57% group B; P  = .05) and a lower prevalence of antiphospholipid antibodies–related pregnancy morbidity (47% group A vs 63% B; P  = .004). The association of hydroxychloroquine with a lower rate of any complication in pregnancy was confirmed after multivariate analysis (odds ratio, 2.2; 95% confidence interval, 1.2–136; P  = .04). Fetal losses at >10 weeks of gestation (2% vs 11%; P  = .05) and placenta-mediated complications (2% vs 11%; P  = .05) were less frequent in group A than group B. Pregnancy duration was longer in group A than group B (27.6 [6-40] vs 21.5 [6-40] weeks; P  = .03). There was a higher rate of spontaneous vaginal labor in hydroxychloroquine-treated women compared with group B (37.3% vs 14.3%; P  = .01). Conclusions Despite the heterogeneity in the 2 groups in terms of systemic lupus erythematosus prevalence and previous pregnancy history, our results support the concept that women with antiphospholipid antibodies may benefit from treatment with hydroxychloroquine during pregnancy to improve pregnancy outcome. The addition of hydroxychloroquine to conventional treatment is worthy of further assessment in a proper designed randomized controlled trial.