The mechanisms responsible for the lower relapse rate of multiple sclerosis during pregnancy and an increased relapse rate during the postpartum period are still undefined. Putative explanations include pregnancy-related alterations in the function of the immune system, such as a shift towards T helper (Th)2-type immune reactivity and expansion of regulatory T lymphocytes.^1,2 Analysis of the cerebrospinal fluid (CSF) offers a unique opportunity to characterise immunological pathways in the pathogenesis of multiple sclerosis. The inflammatory activity in the central nervous system (CNS) of patients with multiple sclerosis is reflected in the composition of CSF cells and one hallmark of the disease is the production of intrathecal antibodies. The aim of our study was to investigate the alterations that take place in the CSF of patients with multiple sclerosis during pregnancy. To our knowledge, no previous attempts have been made to analyse the components of the CSF of pregnant patients with multiple sclerosis.

METHODS

The study included six patients with relapsing remitting multiple sclerosis, who were enrolled at a time of known pregnancy status. Follow-up with recording of relapses continued until 6 months after the delivery. Only one of the patients (case 5) was undergoing disease-modifying treatment (subcutaneous interferon (IFN)β-1a) before pregnancy, and the drug was discontinued 3 months before the onset of pregnancy. No immunomodulatory …