Abstract
Background Systemic Lupus Erythematosus (SLE) is predominant in women of childbearing age. Careful family planning is required because SLE disease activity and SLE therapy affect the risk of adverse pregnancy outcomes (APOs). This study investigates prevalence and risk factors of APOs (Pre-term birth (PB), pre-eclampsia/eclampsia).
Methods We conducted a cohort study of pregnancies in women with SLE using the National Health Insurance Service (NHIS) database of Korea (2002–2018). SLE was defined as having both ICD-10 codes (M32.0) and rare intractable disease registration codes (V136). Pregnancies from 2005 to 2017 of women aged 15–49 with SLE-related visits at least a year before the Last Menstrual Period (LMP) were included. Logistic regression models for APOs were conducted, including age, SLE-related clinical characteristics before pregnancy (SLE treatments during 3 months before LMP, number of SLE-related outpatient visits or hospitalization), use of immunosuppressants (mycophenolate mofetil (MMF)/methotrexate (MTX)/cyclophosphamide (CYC)) during pregnancy, comorbidities, parity, and obstetric complications.
Results In 5,044 total pregnancies, mean age was 32.4 years (standard deviation 4.3). PB and pre-eclampsia/eclampsia were 11.0% and 4.3%, respectively. Only 42.3% were prescribed hydroxychloroquine (HCQ) during pregnancy, and 2.8% were prescribed MMF/MTX/CYC during 1st trimester. PB was associated with more than 10 SLE-related visits (Adjusted Odds Ratio [AOR] 2.15, 95% Confidence Interval [CI] 1.64–2.81) in previous year and pre-eclampsia/eclampsia (AOR 2.02, 95% CI 1.42–2.85). The risk of pre-eclampsia/eclampsia was associated with MMF/MTX/CYC use during the first trimester (AOR 3.55, 95%CI 1.32–9.57), hypertension (AOR 2.70, 95%CI 1.93–3.77), and steroids use during 3 months before LMP (≥7.5mg AOR 1.89, 95%CI 1.28–2.79 vs. 0mg).
Conclusions The limited use of HCQ during pregnancy was observed in study period. PB was associated with higher number of SLE visits before pregnancy and pre-eclampsia/eclampsia. Pre-eclampsia/eclampsia was associated with MMF/MTX/CYC use during the first trimester, hypertension, and steroid use, reflecting the effects of maternal comorbidities and SLE disease activity.
