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Study Suggests Pregnancy Delays Onset of MS Symptoms by More Than 3 Years

September 22, 2020

Understanding Why May Lead to Insights into the Disease
In a study of 2,557 women with MS, those with a previous pregnancy experienced their first MS-like symptom (clinically isolated syndrome – CIS) an average of more than 3 years later than those who had never been pregnant. Having more than one pregnancy was not associated with additional delays in onset.
  • Pregnancy is characterized by a dampening of immune responses and the presence of potentially nervous system-protective hormones, both of which protect the developing fetus. The combined anti-inflammatory and neuroprotective effects of pregnancy appear to have a positive impact on MS as well. The mechanisms for this impact are not fully understood.
  • This team looked at 2,557 women with MS enrolled in MSBase, an international registry that follows the medical history of more than 70,000 people with MS. Among this group, 1,176 had experienced at least one pregnancy.
  • This study adds to a growing body of research attempting to uncover the influences of pregnancy, breast feeding, and sex hormones on the risk, onset and course of MS. Better understanding the mechanisms behind these influences may lead to new pathways for treating or preventing MS.
  • MS often occurs in women of childbearing age, and family planning for someone with MS involves many unique considerations. Read more about pregnancy and reproduction issues in MS.
“Association of Pregnancy With the Onset of Clinically Isolated Syndrome” is published by Ai-Lan Nguyen, MBBS (Royal Melbourne Hospital) and colleagues in JAMA Neurology (Published online September 14, 2020).

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis, and there is currently no cure for MS. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. An estimated 1 million people live with MS in the United States. Most people with MS are diagnosed between the ages of 20 and 50, and it affects women three times more than men.


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