Previous pregnancy outcome is an important determinant of subsequent pregnancy outcome in women with systemic lupus erythematosus

Abstract

Women with systemic lupus erythematosus (SLE) have increased adverse pregnancy outcomes. The reasons for these problems include maternal disease, clinical or serologic activity, medication use, and residual organ impairment from prior disease flares. In retrospective studies, pregnancy data are often treated cross-sectionally, with births rather than mothers as the unit of analysis. Multiple pregnancies from the same mother may be highly correlated with each other. In an unmatched retrospective study, the first two pregnancy outcomes in lupus patients with anticardiolipin antibody (anti-CL IgG or IgM isotype) (cases N = 47) and without anticardiolipin antibody (controls, N = 125) were assessed according to birth order. A good outcome was defined as a full-term (> 38 weeks) live birth without neonatal complications. All other pregnancy outcomes were considered adverse outcomes. Therapeutic abortions and ectopic or molar pregnancies were excluded. Both cases and controls with an adverse outcome in their first pregnancy had at least a 50% chance of another adverse outcome in their second pregnancy. Cases with a late miscarriage (fetal loss at 14 to 20 weeks' gestation) in their first pregnancy had the highest risk, 80%, of an adverse outcome in their second pregnancy. Both previous pregnancy loss and anti-CL antibody status should be considered in the analysis of pregnancy outcomes in women with SLE.