Postpartum relapse risk in multiple sclerosis: a systematic review and meta-analysis

Area of Science:

• Neurology
• Reproductive Medicine
• Epidemiology

Background:

• The impact of pregnancy on multiple sclerosis (MS) disease activity remains debated, with historical data suggesting reduced relapses during pregnancy and increased relapses postpartum.
• Recent studies present conflicting findings, necessitating a comprehensive analysis of postpartum relapse rates in women with MS.

Approach:

• A systematic review and meta-analysis were conducted using MEDLINE and Epistemonikos databases, searching for studies on 'motherhood choice in MS' in March 2022.
• Included were 11 cohort studies encompassing 2739 pregnancies, assessing MS relapse activity (annualised relapse rate) at 3, 6, 9, and 12 months postpartum.
• Data on disease-modifying therapies (DMTs) and breastfeeding were analyzed as potential influencing factors.

Key Points:

• Women with MS exhibited a significantly elevated relapse rate within the first six months postpartum compared to preconception.
• The incidence rate ratio (IRR) for relapses nearly doubled in the first three months postpartum (IRR 1.87).
• Relapse rates decreased significantly by 10-12 months postpartum (IRR 0.81).

Conclusions:

• A notable increase in MS relapses occurs in the early postpartum period, requiring careful consideration in clinical practice.
• Preconceptional use of highly-effective DMTs (IRR 2.76) was associated with increased postpartum relapse risk.
• Exclusive breastfeeding (risk ratio 0.39) was linked to a reduced risk of postpartum relapses.