Background/Purpose:   Systemic lupus erythematosus (SLE) disproportionately affects women during childbearing years. Given the limited data on perinatal medication use among patients, our objective was to characterize real-world therapy patterns among women with SLE before, during, and after pregnancy.

Methods: Our data include all visits to health professionals and all hospital admissions from Jan 1, 1990 to Dec 31, 2010 and all dispensed medications from Sept 1, 1995 to Dec 31, 2010. The case definition for SLE was: a) diagnosis of SLE on at least two visits within a two-year period between Jan 1996 and Dec 2010 by a non-rheumatologist physician; or b) diagnosis of SLE on at least one visit by a rheumatologist or from hospitalization.  Cases with an ICD-9 code for SLE prior to 1996 were excluded. From this, we assembled a cohort of women, aged 18 or older, with pregnancies ending in a delivery as identified using ICD-9 codes in the hospitalization database. We calculated the estimated date of conception (EDC) as the date of delivery minus 270 days and created the following periods: 1) pre-conception 1 (91-180 days before EDC); 2) pre-conception 2 (90 days before EDC); 3) 1^st trimester; 4) 2^nd trimester; 5) 3^rd trimester; 6) post-delivery 1 (90 days after delivery); and 7) post-delivery 2 (91 – 180 days after delivery). Using information on prescription date and days’ supply, we determined the use of medications including disease modifying anti-rheumatic drugs (DMARDs), biologics, glucocorticosteroids, and non-steroidal anti-inflammatory drugs (NSAIDs) for each period.

Results: We identified 100 pregnancies with delivery date at age 18-45 and at least 450 days after SLE onset, from an incident cohort of 4,297 women with SLE. At delivery, mean age was 32.1 ± 4.4 years and SLE duration was 3.8 ± 1.9 years. We tabulated the proportion of exposed pregnancies according to each period and medication class (Table). The majority of DMARD pregnancy exposures were to hydroxychloroquine and/or chloroquine (41 to 45% of exposed pregnancy trimesters).  In contrast to the decline in use during pregnancy compared to pre-conception periods for DMARDs and NSAIDs, we observed an increase in glucocorticosteroid exposures during pregnancy, as well as post-delivery.

Conclusion: This population-based study provide data on real-world patterns of perinatal medication use among women with SLE. Findings emphasize the importance of counseling women regarding childbearing decisions as well as the need for evaluation of the risk-benefit profiles of medications in pregnancy.