Changes in Rheumatoid Arthritis Pharmacotherapy During Pregnancy

Rheumatoid arthritis (RA) is a progressive and chronic inflammatory disease that preferentially attacks the joint synovium.¹ Like other rheumatic diseases, RA is more prevalent in women than men, with a female-to-male ratio of 3:1.²  While the onset of RA usually occurs in women after the age of 40 years, a substantial number of women with RA are of childbearing age.³ It is becoming increasingly common for women with RA to contemplate pregnancy or become pregnant as the average maternal age rises¹ and as RA patients are increasingly free of debilitating disease due to aggressive, early treatment with conventional and/or biologic disease-modifying antirheumatic drugs (DMARDs). While the course of disease in pregnant RA patients is generally good, this population presents unique challenges to the practicing clinician.

Remission During Pregnancy

Decreases in RA disease activity during pregnancy have been reported in 75% to 90% of patients, and disease activity returns to baseline in 90% of pregnant patients postpartum.^4,5 The phenomenon of RA remission during pregnancy, first described in 1938, has been ascribed to immunologic alterations that prevent rejection of the fetus.⁶  The widespread belief that RA remits in pregnancy may have given false assurance to clinicians whose approach to pregnant patients with RA was to withhold medication entirely, a practice that persists among some clinicians today.⁴

Recent studies indicate that pregnancy is associated with clinical improvement in only 40% to 66% of RA patients.¹ UK researchers who used standardized assessments to measure disease activity found that just 16% of patients achieved complete remission during pregnancy.⁷ 

 Determining which patients may develop flares during pregnancy and immediately after presents a challenge, according to Bindee Kuriya, MD, a rheumatologist and researcher from the University of Toronto, who has a special interest in RA and pregnancy. In an email interview with Rheumatology Advisor, Dr Kuriya stated, “Since most women will choose to stay off medications or hold them during pregnancy, coming up with a plan to resume DMARDs/therapies postpartum is crucial, especially in those who will be at high risk for disease flares.”