BACKGROUND Planning pregnancy in patients with active multiple sclerosis (MS) is highly challenging because treatment withdrawn may be associated with dramatic disease reactivation. OBJECTIVE To compare two strategies for women with active MS who were planning pregnancy: stopping natalizumab (1) at the end of the first trimester and (2) at conception. METHODS Standardized strategy for women with active MS was initiated in our department. Maintenance of natalizumab until the end of first trimester was recommended ("secured first trimester" (SFT)). When patients refused, they were advised to continue until conception ("secured conception" (SC)). Predictors of disease activity during pregnancy were assessed. RESULTS Forty-six pregnancies were prospectively followed (30 with SFT and 16 with SC). One congenital anomaly occurred in the SC group. The proportions of patients with relapse and disability progression during pregnancy were lower in the SFT than in the SC group (3.6% vs 38.5%, p < 0.005 and 3.6% vs 30.8%, p < 0.05, respectively). Predictors of relapse and disability progression during pregnancy were the time when natalizumab was stopped (conception vs end of first trimester) and the number of relapses during the year before natalizumab. CONCLUSION Maintaining natalizumab during the first trimester may reduce the risk of disease reactivation during pregnancy in patients with active MS.

中文翻译：

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在活动性多发性硬化症的妊娠头三个月期间维持那他珠单抗

背景 活动性多发性硬化症 (MS) 患者的计划妊娠极具挑战性，因为停止治疗可能与疾病的严重复发有关。目的 比较针对计划怀孕的活动性 MS 女性的两种策略：停止那他珠单抗 (1) 在妊娠头三个月末和 (2) 在受孕时。方法 我们部门启动了针对活动性 MS 女性的标准化策略。建议将那他珠单抗维持到孕早期结束（“安全孕早期”（SFT））。当患者拒绝时，建议他们继续受孕（“安全受孕”（SC））。评估了妊娠期间疾病活动的预测因素。结果 对 46 次妊娠进行了前瞻性随访（30 次为 SFT，16 次为 SC）。SC组发生了一种先天性异常。SFT 组妊娠期间复发和残疾进展的患者比例低于 SC 组（分别为 3.6% 对 38.5%，p < 0.005 和 3.6% 对 30.8%，p < 0.05）。妊娠期间复发和残疾进展的预测因素是那他珠单抗停止的时间（受孕与孕早期结束）和那他珠单抗前一年的复发次数。结论 在孕早期维持那他珠单抗治疗可能会降低活动性 MS 患者孕期疾病再激活的风险。妊娠期间复发和残疾进展的预测因素是那他珠单抗停止的时间（受孕与孕早期结束）和那他珠单抗前一年的复发次数。结论 在孕早期维持那他珠单抗治疗可能会降低活动性 MS 患者孕期疾病再激活的风险。妊娠期间复发和残疾进展的预测因素是那他珠单抗停止的时间（受孕与孕早期结束）和那他珠单抗前一年的复发次数。结论 在孕早期维持那他珠单抗治疗可能会降低活动性 MS 患者孕期疾病再激活的风险。