Impact of Systemic Lupus Erythematosus on Pregnancy Analysis of a Large 10-Year Longitudinal Mexican Cohort

Background: Pregnancy in patients with systemic lupus erythematosus is considered a high risk one since it is associated with a higher rate of maternal-fetal complications compared with the pregnancies in healthy women. Objectives: The aim of this study was to describe the maternal-fetal outcomes in a cohort of Mexican patients with systemic lupus erythematosus and to identify risk factors associated with adverse maternal and fetal outcomes. Patients and Methods: A cohort of pregnant lupus patients was analyzed. Maternal-fetal complications were described, and clinical, biochemical, and immunological variables associated with obstetric adverse outcomes were studied. Descriptive statistics, comparison of variables using appropriate tests, and finally logistic regression analysis were performed to identify potential risk factors for adverse maternal and fetal outcomes. Results: A total of 351 pregnancies were included in a 10-year period. The most frequently observed maternal adverse outcomes were lupus flare (35%) and preeclampsia (14.5%). Active lupus before pregnancy (hazards ratio [HR], 3.7; 95% confidence interval [CI], 1.1-12.5; p = 0.003) was a predictor for these complications, whereas the use of antimalarial drugs (HR, 0.4; 95% CI, 0.2-0.7; p = 0.007) was a protective factor. The most frequent fetal adverse outcomes were preterm birth (38.1%), miscarriages (10%), and low birth weight babies (28%), and very low birth weight new-borns (11%). Proteinuria in early pregnancy (HR, 7.1; 95% CI, 1.01-50.3; p = 0.04) and preeclampsia (HR, 9.3; 95% CI, 1.7-49.7; p = 0.009) were risk factors associated with these complications. Conclusions: Variables related to systemic lupus erythematosus activity predict an adverse maternal outcome, whereas proteinuria in early pregnancy and preeclampsia are associated with an adverse fetal outcome.