The presence of lupus nephritis additionally increases the risk of preeclampsia among pregnant women with systemic lupus erythematosus

INTRODUCTION: Pregnant women with systematic lupus erythematosus (SLE) have an increased risk of obstetric complications, such as preeclampsia and premature births. Previous studies have suggested that renal involvement could further increase the risk for adverse obstetric outcomes. Aims: The aim of this study was to compare the obstetric outcomes in a Swedish cohort of patients with SLE with and without lupus nephritis (LN). PATIENTS AND METHODS: The study was conducted as a retrospective observational study on 103 women with SLE, who gave birth at the Karolinska University Hospital between the years 2000-2017. Thirty-five women had previous or active LN and 68 women had non-renal lupus. Data was collected from digital medical records. The outcomes that were analysed included infants born small for gestational age (SGA), premature birth, preeclampsia, SLE- or nephritis flare and caesarean section. RESULTS: Women with LN, both with previous and with renal flare during pregnancy suffered from pre-eclampsia more often compared to women with non-renal lupus (25.7% vs 2.9%, p = 0.001) and this complication was associated with premature birth (p = 0.021) and caesarean section (p = 0.035). CONCLUSIONS: Lupus nephritis is a significant risk factor for adverse obstetric outcomes in women with SLE, including preeclampsia. Those patients could benefit from more frequent antenatal controls and more vigorous follow-up.