ABSTRACT
It has been appreciated for decades that the symptoms of patients with autoimmune diseases are affected by pregnancy and the postpartum period. The best characterized observations include those in multiple sclerosis (MS) and rheumatoid arthritis. Patients with these conditions experience clinical improvement during pregnancy with a temporary ‘rebound’ exacerbation postpartum.[1-10] This chapter focuses on mechanisms that may underlie this protection against disease during pregnancy in MS. This phenomenon of an improvement in disease during pregnancy is a unique opportunity to gain insight into MS disease pathogenesis and to capitalize on a naturally occurring situation in which the disease is down-regulated. Understanding disease-modifying mechanisms during pregnancy may lead to the identification of factors with therapeutic potential for MS. Furthermore, the therapeutic potential of an identified factor might be beneficial not only in MS but also in other autoimmune diseases characterized by significant improvement during pregnancy, such as rheumatoid arthritis.
