Factors associated with adverse pregnancy outcomes in patients with systemic lupus erythematosus.

BACKGROUND

Pregnancies in Systemic lupus erythematosus (SLE) are considered high risk and associated with maternal and obstetric complications.

OBJECTIVES

To determine the most important predictors for each of the main adverse pregnancy outcomes in SLE patients.

METHODS

Patients with SLE were retrospectively analysed from 1990 to 2020. Maternal and fetal complications in pregnant women with SLE were retrieved. We compared clinical and analytical characteristics of SLE patients with adverse pregnancy outcomes to controls with SLE diagnosis without adverse pregnancy outcomes. Qualitative data were analysed by Chi-square test and Fisher's exact test. Continuous variables were analysed by using Student's t test. Multiple logistic regression was performed to determine the predictive factors for adverse pregnancy outcomes with adjustment of confounding factors.

RESULTS

135 multiparous women were included (42% with adverse pregnancy outcomes). A total of 57 pregnancies (42%) were linked to adverse outcomes. The occurrence of abortion was correlated with anti-DNAds (β = 0.71, p = 0.04), renal involvement (β = 0.28, p 0.03), antiphospholipid antibodies (APA) (β = 0.29, p 0.03), erythrocyte sedimentation rate (ESR) elevation (β = 0.81, p = 0.02) and C-reactive protein (CPR) elevation (β = 0.91, p = 0.01). Stillbirth was also correlated with renal involvement (β = 0.26, p = 0.04), APA (β = 0.22, p = 0.03) and ESR elevation (β = 0.53, p = 0.02). Preeclampsia was correlated with direct Coombs positivity (β = 0.42, p = 0.01), serositis (β = 0.31, p = 0.02), ESR elevation (β = 0.52, p = 0.03) and CPR elevation (β = 0.32, p = 0.04). Neonatal Lupus was correlated with anti-RNP (β = 0.16, p = 0.03) and anti-Ro/SSA (β = 0.16, p 0.02).

CONCLUSIONS

The most unfavourable pregnancy outcome in women with SLE was spontaneous abortion. Renal involvement, anti-DNAds positivity, antiphospholipid antibody positivity, anti-Ro/SSA, elevated ESR and a younger age at disease onset increased the risk of pregnancy complications.