Natalizumab treatment and pregnancy in multiple sclerosis: A reappraisal of maternal and infant outcomes after 6 years.

To assess the impact of timing of natalizumab cessation/redosing on long-term maternal and infant outcomes in 72 out of the original 74 pregnancies of the Italian Pregnancy Dataset in multiple sclerosis (MS). Maternal outcomes in patients who received natalizumab until conception and restarted the drug within 1 month after delivery ("treatment approach," (TA)) and patients who stopped natalizumab before conception and/or restarted the drug later than 1 month after delivery ("conservative approach," (CA)) were compared through multivariable Cox regression analyses. Pediatric outcomes were assessed through a semi-structured questionnaire. After a mean follow-up of 6.1 years, CA (hazard ratio (HR) = 4.1, 95% CI 1.6-10.6, Our data confirm that TA reduces the risk of disease activity; we did not observe an increase in major development abnormalities in the child.