Risk of relapses during pregnancy and post-partum period among multiple sclerosis patients (P4.368)

Objective: To assess the relapse risk (RR) during pregnancy and post-partum period in multiple sclerosis (MS) patients and examine the relationship between the use of DMTs, washout periods and RR. Background: MS relapse risk is often reduced during pregnancy. However, disease reactivation may occur following withdrawals of disease modifying therapies (DMTs) prior or at the time of pregnancy confirmation Design/Methods: A cross-sectional cohort study was conducted using data from two MS registries in Kuwait and Lebanon. Data on demographics and clinical characteristics of pregnant women including relapses, prior use of DMTs, and pregnancy outcomes were extracted Results: Medical records of 164 pregnancies (132 MS patients) were reviewed. Mean age and mean disease duration at the time of pregnancy confirmation were 32.4 ± 5.3 and 7.8 ± 4.7 years respectively. Most patients (91.7%; n = 121) were on DMTs in the year prior to pregnancy and the most prescribed drug was beta interferons (46.2%), followed by fingolimod (20.5%) and natalizumab (18.9%). RR during pregnancy was 15.2% (25/164; 95% CI: 9.9% – 22.5%). The majority of relapses occurred either during the 1 st (RR = 40%; 95% CI: 19.2%–73.6%) or 3rd (RR = 52 %; 95%CI: 27.8%–88.9%) trimester. RR during post-partum period was 15.9% (26/164; 95%CI: 10.4–23.2). On average these relapses occurred within 9.7 (± 9.4) weeks of delivery. A higher RR was for pregnancies that were pre-exposed to fingolimod (25%; 8/32) or natalizumab (20%; 6/30). The mean washout period (week) was significantly ( p = 0.009) longer among subjects with relapses (9.8 ± 6.0; n = 141 versus 2.6 ± 4.0; n = 25). Conclusions: Relapse risk during pregnancy was higher than expected. Most relapses clustered in the first and third trimester. Longer washout periods prior to conception was associated with increased RR especially in fingolimod-treated patients Disclosure: Dr. Alroughani has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Bayer, Biogen, Merck, Novartis, Roche, Sanofi-Genzyme. Dr. Alroughani has received research support from Biogen, Novartis, Sanofi-Genzyme. Dr. Akhtar has nothing to disclose. Dr. Zeineddine has nothing to disclose. Dr. Alowayesh has nothing to disclose. Dr. EL Kouzi has nothing to disclose. Dr. Ahmed has nothing to disclose. Dr. Behbehani has nothing to disclose. Dr. Khoury has received research support from Novartis Pharmaceuticals. Dr. Al-Hashel has nothing to disclose. Dr. Yamout has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Bayer, Biogen, Genzyme, Merck-Serono, Novartis, and Genpharm.