Fetal and maternal outcomes of 70 pregnancies in 48 women with lupus nephritis were retrospectively analyzed. In 13 women, lupus nephritis developed during pregnancy (group A). In 38 patients with known lupus nephritis (including 3 patients in group A who had another pregnancy), 57 pregnancies occurred. In 6 patients, a therapeutic abortion was performed. The remaining 51 pregnancies were considered pregnancies in lupus nephritis (group B). Fetal loss was 36% (38%, group A; 35%, group B); it decreased from 46% in the 1970s to 30% in the last decade. Among 41 live births, there were 13 preterm deliveries and 28 full-term deliveries. At multivariate analysis, proteinuria (P = 0.025), arterial hypertension (P = 0.05), and antiphospholipid antibodies (P = 0.01) were independent predictors of fetal loss. In group A, 3 patients developed acute renal failure, irreversible in 1 patient (7.7%); all other patients recovered after steroid and immunosuppressive therapy. In group B, 12 renal flares and 1 extrarenal flare developed during pregnancy or the postpartum period. Two patients progressed to irreversible renal failure (3.9%), and 1 of the 2 patients died. All other patients recovered. The incidence of renal flares before or during pregnancy was not different (P = 0.51). Renal quiescence at the onset of pregnancy was the only predictor of favorable maternal outcome. Proteinuria, hypertension, and positivity of antiphospholipid antibodies are independent predictors of adverse fetal outcome. Quiescence of renal disease is the only predictor of favorable maternal outcome. Copyright 2002 by the National Kidney Foundation, Inc.