The Response Study: A French registry on pregnancy in women with MS and related disorders and their children up to 6 years-Protocol, recruitment status, and baseline characteristics

Background: Counseling on pregnancy is still challenging, particularly regarding the use of disease-modifying treatments (DMTs). We are lacking long-term outcomes in children exposed to DMTs. Objectives: This study aimed to set up a French pregnancy registry for women with multiple sclerosis (MS) and related disorders nested within the Observatoire Francais de la Sclerose en Plaques (OFSEP) cohort. Methods: Prospective, observational, multicentric, epidemiological study in France. Neurological visits are organized according to routine practice. Data are collected on the OFSEP minimal datasheet. Auto-questionnaires on pregnancy are completed by patients at Months 5-6 and 8 during pregnancy, and Months 3, 6, and 12 postpartum. A specific survey on analgesia is completed by anesthesiologists. Pediatric data are collected from the child's health book, where visits on Day 8, Month 9, and 24 are mandatory. Parents complete neurodevelopmental questionnaires at Year 1, Years 2 and 6. Results: The RESPONSE study started in August 2019. On 7 April 2023, 515 women were included. Baseline demographics are presented. Conclusions: RESPONSE will provide rich information on the global management of pregnancy in France and prospective data on children until the age of 6 years, exposed or not to a DMT, including data on neurodevelopment that can be compared to the general population.