Pregnancy Outcomes in Women With Rare Autoimmune Diseases

To examine pregnancy outcomes and pregnancy-related health service utilization among women with rare autoimmune diseases.

This population-based cohort study of an Australian obstetric population (2001-2011) used birth records linked to hospital records for identification of rare autoimmune diseases including systemic vasculitis, vasculitis limited to the skin, Sjögren's syndrome, systemic sclerosis, Behçet's disease, polymyositis/dermatomyositis, and other systemic involvement of connective tissue. We excluded births in women with systemic lupus erythematosus or rheumatoid arthritis as well as births occurring ≥6 months before the diagnosis of the rare autoimmune disease. Modified Poisson regression was used to compare study outcomes between women with autoimmune diseases and the general obstetric population.

There were 991,701 births, including 409 births (0.04%) in 293 women with rare autoimmune diseases. Of the 409 births, 202 (49%) were delivered by cesarean section and 72 (18%) were preterm; these rates were significantly higher than those in the general obstetric population (28% and 7%, respectively). Compared to the general population, women with autoimmune diseases had higher rates of hypertensive disorders, antepartum hemorrhage, and severe maternal morbidity and required longer hospitalization at delivery, more hospital admissions, and tertiary obstetric care. Compared to other infants, those whose mothers had a rare autoimmune disease were at increased risk of admission to a neonatal intensive care unit, severe neonatal morbidity, and perinatal death.

While the majority of women with rare autoimmune diseases delivered healthy infants, they were at increased risk of having both maternal complications and adverse neonatal outcomes, suggesting that their pregnancies should be closely monitored.