Mary A. De Vera
The use of biologic medications for autoimmune diseases prior to or during pregnancy is not associated with an increased risk for preterm delivery or infants that are small for gestational age, according to findings published in the Annals of the Rheumatic Diseases.
“Several types of arthritis are known to affect women more commonly than men and can start as early as during the child-bearing years,” Mary A. De Vera, PhD, of the University of British Columbia, told Healio Rheumatology. “Our previous research showed that more and more women with arthritis are using biologic treatments to manage their disease and even continuing these medications throughout pregnancy. There is limited research about the safety of using biologics during pregnancy, especially since pregnant women are not studied in clinical trials.”
To determine the risk for preterm delivery and births that are small for gestational age among women using biologics to treat autoimmune diseases, the researchers drew information from the Population Data British Columbia repository, which contains individual-level, de-identified longitudinal data on all health services of the 4.6-million-person population of British Columbia.
Figure 1. Treatment with biologic medications for autoimmune diseases prior to or during pregnancy is not associated with an increased risk for preterm delivery or infants that are small for gestational age, according to researchers.
De Vera and colleagues focused on 6,218 women who had been diagnosed with an autoimmune disease, representing 8,607 pregnancies. Among those women, 109 — covering 120 pregnancies — had taken biologics during or 3 months prior to pregnancy. The researchers matched each biologic-exposed pregnancy with five unexposed pregnancies using high-dimensional propensity scores.
According to the researchers, after propensity-score matching with 600 pregnancies in which the mothers had not taken biologics, the odds ratio for the association between exposure and preterm delivery was 1.13 (95% CI, 0.67-1.9). In addition, the association between biologic use and births that were small for gestational age was 0.91 (95% CI, 0.46-1.78). The researchers noted that sensitivity analyses did not result in any significant changes in the results.
“The key takeaway is that these medications do not appear to cause problems like preterm deliveries or having babies that are small for their gestational age, and rather, women who use biologics around the time of pregnancy or during pregnancy had similar pregnancy outcomes as women who weren’t using these medications,” De Vera said. “This is reassuring for patients who may be prescribed biologics to manage their inflammatory disease. It shows that staying on these treatments throughout pregnancy will allow them to maintain control of disease without being worried about the drugs causing harm.”
According to De Vera, the findings can help physicians and patients plan for pregnancy and inform them on how certain treatments may affect the health of their infant.
“Knowing that biologics could be a compatible treatment option is important for women with inflammatory disease and physicians caring for these women,” she said. “This information could become part of their discussion on balancing risks and benefits of treatments during pregnancy.” – by Jason Laday
Disclosure: The researchers report funding from The Arthritis Society.