MS Treatments and Your Pregnancy: A Comprehensive Guide to What's Safe, What's Not, and How to Move Forward Confidently

Can I Take MS Medication When I’m Nursing?

“Exclusive breastfeeding reduces the risk of a relapse, so we encourage significant breastfeeding,” says Allan Akerman, MD, an OB/GYN at Providence Saint Joseph Hospital in Orange County, CA.

Your doctor will consider if a medication can pass into your breast milk, and if so, how much is absorbed into your baby’s system.

In some cases, your doctor will also have to decide if the help you’ll get from an MS treatment outweighs the possible risks to your baby.

“These are nuanced discussions and highly individual to each mother-baby pair,” says Patrick.

Here’s a look at some common MS treatments and what experts know about taking them when you’re pregnant or nursing.

Injectables

“Traditional injectables, which are the longest-used DMTs, have the most long-term data for use during pregnancy,” says Joseph Canterino, MD, a board-certified maternal and fetal medicine specialist at Hackensack Meridian Jersey Shore University Medical Center in Neptune, NJ.

Interferon beta 

Safe during pregnancy? Yes. There’s no data to show it can cause birth defects.

Safe while nursing? Yes.

Glatiramer acetate (Copaxone)

Safe during pregnancy? Yes.

Safe while nursing? Yes. Only low amounts get into your breast milk, and your baby probably only absorbs a small part.

Corticosteroids

If you have a relapse while you’re pregnant, your doctor could prescribe steroids.

Safe during pregnancy? Generally safe in small doses.

• Avoid corticosteroids during the first trimester. There’s a small chance your baby could be born with a cleft palate.
• In your second and third trimesters, methylprednisolone, prednisolone, and prednisone are considered safe. But they could raise your chance of preterm birth and low birth weight.

Safe while nursing? Yes, but pump and discard your breast milk for at least four hours after you have steroids.

Monoclonal Antibodies

These drugs affect your body even after you stop taking them. “Monoclonal antibody treatments that suppress parts of the immune system can pass through the placenta, leading to a temporary but significant depletion of B-cells in your newborn,” Canterino says.

That can make it harder for your baby’s immune system to work the way it should.

Alemtuzumab (Campath ®)

Safe during pregnancy? No. It’s not known whether it could harm your baby.

• If you get pregnant while taking alemtuzumab, stop it right away. Tell your doctor. 
• You and your baby will be closely monitored if you get pregnant within one month of stopping alemtuzumab.

Safe while nursing? No.

Natalizumab (Tysabri ®)

Safe during pregnancy? No, but your doctor may feel that the benefits to you outweigh the risks.

• If your MS is active, your doctor may want you to keep taking it during pregnancy.
• Studies found that babies exposed to natalizumab during the third trimester had blood issues, such as low red blood cells or platelets. But they didn’t need treatment and got better on their own.
• If you get pregnant while on natalizumab, tell your doctor right away. They’ll probably change how often you get this drug and its dosage.

Oral MS Medications

You take these drugs by mouth to help prevent a relapse. They include S1P receptor modulators, which affect your immune system. Most of the time, you should avoid these drugs if you’re pregnant or trying to get pregnant. They include:

Cladribine (Mavenclad ®)

Safe during pregnancy? No. Cladribine can harm your unborn baby.

• Birth control pills won’t work well when you take this drug. Use another form of birth control to keep from getting pregnant while you take it.
• Try not to get pregnant for at least six months after you stop cladribine. If you do, let your doctor know right away.

Safe while nursing? No. Stop breastfeeding when you use this drug, and wait one week after your last dose to start.

Fingolimod (Gilenya ®)

Safe during pregnancy? No. This treatment can harm your baby. Your doctor will need to confirm you’re not pregnant before they prescribe you this drug. 

• Use birth control for at least two months after you stop this treatment.
• If you do get pregnant while taking fingolimod, tell your doctor. They’ll need to do an ultrasound to see how your baby is doing.

Safe while nursing? No.

Ozanimod (Zeposia ®)

Safe during pregnancy? No. 

• Use birth control for at least three months after you stop this treatment.
• One small study found that when given in early pregnancy, ozanimod didn’t cause increased harm to moms or their babies. But much more research needs to be done to prove this.

Safe during pregnancy? Probably not. Talk to your doctor.

• This small-molecule drug could cross the placenta and affect your baby’s growth. More studies need to be done to see how it could affect your baby. 
• Because of the lack of data, taking it while pregnant is generally not advised.

Safe while nursing? Probably not. Dimethyl fumarate does get into your breast milk, and there isn't a lot of research on how it affects babies. If your doctor wants you to take it, wait at least four to five hours before you feed your baby.

Physical Therapy

Physical therapy can improve your strength, balance, and posture. It can also help with MS symptoms such as fatigue, bladder issues, stiffness, and pain.

Safe during pregnancy? Yes. “Patients with MS can and should continue or start safe physical therapy during pregnancy,” says Canterino.

• A trained physical therapist can safely tailor exercises to your needs.
• You may have “hands-on” sessions, as well as exercises you can do at home.

Safe while nursing? Yes.

Over-the-Counter Treatments 

At times, you could also use nonprescription products such as fiber supplements, vitamins, pain relievers, and topical pain treatments to help manage your MS symptoms.

Don’t assume that they’re safe to use just because they don’t require a prescription.

“Go case by case and review each of them with your doctor,” Akerman says.

Ask for a list of common supplements and OTC products you should avoid, as well as safe options to take when you’re pregnant or nursing.

“It’s also important to consider any drug interactions that may occur with your MS treatment regimen,” Patrick says.

How to Safely Manage MS Symptoms

Talk to your doctor about other things you can safely do to manage your MS symptoms during pregnancy and while you nurse your baby.

For instance, it can help to:

• Use assistive devices, such as canes or splints.
• Adjust your home so it’s easier to get around.
• Get regular exercise.
• Get support from family and friends.
• Work with a speech therapist or occupational therapist.
• Join a support group of other parents with MS.
• See a therapist to manage your stress levels.

The following chart can help you keep track of what treatments are safe if you're pregnant or nursing: