Pregnancy in lupus nephritis.

Background: Fetal and maternal outcomes of 70 pregnancies in 48 women with lupus nephritis were retrospectively analyzed.

Methods: 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).

Results: 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.

Conclusion: 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.