Which MS treatments are safest during pregnancy?

Question

Hello doctor,

My 32-year-old wife was diagnosed with multiple sclerosis 18 months ago after experiencing vision problems and numbness in her left leg. She has been on Glatiramer acetate injections but continues to have relapses every three to four months.

Her most recent MRI showed two new brain lesions and several active lesions in the spinal cord. Her neurologist has recommended switching to natalizumab infusions, but we learned that she is JC virus positive, which increases the risk of a serious brain infection. She had hoped to become pregnant this year, but most MS medications seem too dangerous during pregnancy.

Her symptoms have worsened significantly—she struggles to walk long distances, her hands tremble when she tries to write, and on some days, her arms are so weak that she cannot hold our two-year-old son. She also suffers from severe fatigue, sleeping up to 12 hours a night, yet still feeling exhausted.

Multiple sclerosis has completely changed our lives, and I am not sure how to help her cope. Can pregnancy actually make MS symptoms better or worse, and are there any treatments considered safe if she decides to become pregnant?

Please help.

Thank you.

Answer 1

Hello,

Welcome to icliniq.com.

I understand your concern.

I am really sorry you and your wife are going through this. It sounds overwhelming.

In her case, the relapses despite glatiramer acetate and the new active lesions on MRI mean the disease is more aggressive and does require stronger therapy, but you are right that Natalizumab carries a risk of PML(progressive multifocal leukoencephalopathy) (a serious brain infection) in JC(human polyomavirus) virus-positive patients, so that risk-benefit decision is very important.

Regarding pregnancy, it is true that many women with MS(multiple sclerosis) experience fewer relapses during pregnancy, particularly in the second and third trimesters, because of natural immune changes, but there is often a rebound increase in relapses in the first few months after delivery.

For women who want to conceive, the safest disease-modifying treatments are usually glatiramer acetate or interferon beta, which have the most reassuring pregnancy safety data.

Stronger agents like Natalizumab, Fingolimod, or Ocrelizumab are generally not recommended during pregnancy, though in very aggressive disease, sometimes Natalizumab is continued until late pregnancy under close monitoring.

Fatigue, weakness, and tremor are unfortunately common MS symptoms, but supportive treatments such as physical therapy, occupational therapy, fatigue management strategies, and sometimes medications like amantadine for fatigue or baclofen for spasticity can make a real difference. Coping is hard on both partners, so involving an MS specialist, fertility counselor, and mental health support may help you both feel less alone in this.

I hope this helps.

Kindly follow up if you have more concerns.

Thank you.

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