Birth Outcomes and Rehospitalizations Among Pregnant Women With Rheumatoid Arthritis and Systemic Lupus Erythematosus and Their Offspring.

Objective: To compare obstetric/birth outcomes and rehospitalization among women with and without rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) and their infants.

Methods: This population-based retrospective cohort study identified women with RA (n = 1,223) and SLE (n = 1,354) and unexposed women with singleton births 1987-2014 in Washington State in linked vital hospital discharge records. Outcomes, including cause-specific hospitalizations <2 years postpartum, were compared by estimating adjusted relative risks (RRs) and cause-specific rehospitalization hazard ratios (HRs) with 95% confidence intervals (95% CIs).

Results: We observed increased risks of several adverse outcomes; RRs were often greatest for SLE. Women with RA/SLE more often required rehospitalization, most notably at <6 months postpartum (RA: 4% versus 2%; RR 2.22 [95% CI 1.62-3.04]; SLE: 6% versus 2%; RR 2.78 [95% CI 2.15-3.59]). Maternal postpartum rehospitalization was greatest for musculoskeletal conditions (RA: HR 19.1 [95% CI 13.6-26.8]; SLE: HR 29.8 [95% CI 22.1-40.1]). Infants of women with SLE more often had malformations (9% versus 6%; RR 1.46 [95% CI 1.21-1.75]), and increased mortality at <2 years (RR 2.11 [95% CI 1.21-3.67]). Infants of women with SLE also experienced more frequent rehospitalizations in their first year of life.

Conclusion: Women with RA or SLE and their infants experienced adverse outcomes, particularly infants of women with SLE. Maternal/infant rehospitalization was more common; most marked in the early months postpartum. Close follow-up during these time periods is crucial to minimize adverse outcomes.