Disease course after pregnancy in women with progressive multiple sclerosis symptoms

Background: The impact of pregnancy on disease outcomes has not been characterised in women with progressive multiple sclerosis (MS) phenotypes. This study aimed to describe the clinical characteristics and disease course of women who experienced a pregnancy after a diagnosis of primary progressive MS (PPMS) or secondary progressive MS (SPMS). Methods: This multicentre observational cohort study utilised data from the international MSBase Registry extracted on 2 June 2024. Expanded Disability Status Scale (EDSS) scores of women with progressive MS were assessed up to 10 years postpartum and compared to those of propensity score–matched women with progressive MS without a pregnancy history. Results: In total, 138 women with 164 pregnancies were included in the study, comprising 75 women with PPMS and 63 with SPMS. Of these, 24 women with PPMS and 47 with SPMS had longitudinal peri-pregnancy EDSS assessments and were included in the analysis of disability scores. A history of pregnancy was not associated with a significant difference in long-term disability trajectories in women with either PPMS (estimate = −0.02; 95% confidence interval (CI) = −0.07 to 0.04) or SPMS (estimate = 0.00; 95% CI = −0.02 to 0.03). Conclusion: A history of pregnancy is not associated with a significant difference in long-term disability in women with progressive MS symptoms.