Having a Baby When You Have MS: Your Medication Safety Guide

Thinking about growing your family is an exciting time. But when you have multiple sclerosis (MS), that excitement can come with big questions: Is it safe for my baby? And what about my own health?

According to maternal and fetal medicine specialist Joseph Canterino, M.D., of Jersey Shore University Medical Center, a healthy pregnancy with MS is absolutely possible. 

Multiple Sclerosis and Pregnancy

Having MS doesn't usually impact your ability to get pregnant, but a safe and healthy journey requires careful planning with your doctors.

Partnering Closely with Your Doctors

Making the decision to grow your family can make anyone feel anxious or fearful of what’s to come, especially if you have MS.

“It’s normal to be worried; just know you’re not alone,” says Maya Madhavan, M.D., neurologist and MS specialist at Jersey Shore. “It’s so important that you partner closely with your neurologist and OBGYN at this time.”

That partnership includes talking about your feelings, too. "Your emotional health is just as important as your physical health," adds Dr. Madhavan. "Pregnancy brings a lot of changes, so please tell your doctor if you notice you're feeling more sad or anxious than usual. We are here to support you."

Before becoming pregnant, you’ll want to discuss the medications you’re taking with your doctor, as some may not be safe for pregnancy.

Can I Take MS Medicine While Pregnant? 

“Deciding to use MS medicine during pregnancy is a choice that you and your doctor make as a team,” says Dr. Canterino. “We have to weigh the good things against the possible risks for both the mother and baby.” 

Disease-modifying treatments (DMTs) work against MS by calming down mom’s immune system, and unfortunately, can have a similar effect on the baby. 

“Our main job is to find a balance: we want to keep the mother's MS stable while also protecting the baby from any medicine that could be harmful,” Dr. Canterino adds.

Here are some of the concerns with taking MS medications while pregnant:

• Birth defects: Some MS medications are known to cause severe disabilities, and must be stopped well before you try to get pregnant. 

• It’s essential to meet with your doctor before getting pregnant. 
• Dr. Canterino advises that you sit down with your doctors to discuss your current medications. Some may need to be stopped before getting pregnant – this gives the medicine time to “wash out” of your body.

• Impact on the immune system: Some medications can pass through the placenta and weaken the baby’s immune system. This might mean waiting longer for some of the baby's first shots.

• Growth risks: 

• Certain DMTs are associated with an increased risk of a low birth weight or your baby being small for its gestational age. 
• Some medications can affect how the placenta functions, which may reduce the supply of oxygen and nutrients to the baby, also causing growth risks. 

What are the risks of stopping MS medications?

Although pregnancy often improves MS symptoms, stopping medication can increase the risk of a flare-up after the baby is born.

If you do relapse during pregnancy, your doctor can help determine the best course of action for you and your baby.

How can pregnancy improve symptoms of MS?

“Pregnancy often reduces the risk of MS flare-ups,” says Dr. Madhavan. “Essentially, during pregnancy, the immune system is calmer, so it doesn’t harm the baby. Since MS is caused by an overactive immune system, this calm-down period often helps MS symptoms.” 

Why are some medicines safer than others?

The safety of the medications during pregnancy all comes down to how the medicines are made and how they work in your body. 

Think of the placenta as a filter or a screen between the mom and the baby. While it gives the baby food and oxygen, it can also block out things that might be harmful. 

MS medicines are made of tiny parts called molecules and can vary in size, both large and small. 

• The size of the medicine matters because the placenta acts as a filter. 
• Medications with big molecules have a harder time passing through the placenta to reach the baby. 
• Medications with small molecules can pass through the placenta more easily, making them riskier.

When you take a medicine during pregnancy really matters. A baby is most at risk for birth defects in early pregnancy, so waiting until later lowers this risk.

Disease-modifying therapies are often made of large proteins. Because they are so big, they usually can't pass to the baby until later in the pregnancy. One example is a medication called Glatiramer acetate, which is specially designed so that almost none of it passes to the baby during the entire pregnancy.

Small-molecule drugs, which can more easily pass through the placenta and tend to stay in the body for long periods, are most concerning.

• One example is Teriflunomide – it can stay in the body for up to two years. Because of this, you’d need a special treatment to remove the medicine from your body before trying to have a baby.

The most important thing is to talk with your neurologist and obstetrician before getting pregnant. They can help you make the best plan for you and your baby.

Is it Safe to Do Physical Therapy for MS While Pregnant?

“Yes! Patients with MS can and should continue or start safe physical therapy during pregnancy,” Dr. Canterino says. “Low-impact activities are great for both your physical and emotional well-being.” 

Safe exercises to try:

• Walking
• Swimming
• Stretching
• Prenatal yoga (yoga designed for pregnant women)

Avoid any activities where you might fall or get hit in the stomach. Listen to your body and do what feels comfortable.

Can I Breastfeed if I'm Taking MS Medicine? 

Breastfeeding is a great way to bond and nourish your baby, and it can even lower your risk of a post-partum MS flare-up.

If you’d like to breastfeed, there are safe medication options available. Here are some options that are typically recommended:

• Considered Safe—Glatiramer. A common brand name is Copaxone. Early studies also show that some other large protein medicines (monoclonal antibodies), like ocrelizumab, ofatumumab and rituximab, also seem to be safe. 
• Use with a Plan—Corticosteroids. If you need steroids, they are generally safe in small doses. You should wait two to four hours after breastfeeding to limit the exposure to your baby. 

• Usually Not Recommended—some fumarates and S1P modulators. For some other MS medicines, we don’t have enough information to know if they are safe for the baby. Your doctor will likely tell you not to take them while breastfeeding.

“Because the risk of relapse increases in the first three months after delivery, we aim to restart medications as soon as possible after the baby is born,” says Dr. Madhavan. “But all of this timing will depend on the specific therapy you’re on and your breastfeeding plans.” 

Always ask your doctor what is right for you.

Planning for Treatment Days

If your MS treatment is given through an IV (this is called an infusion), you may receive other medications right before your treatment, such as corticosteroids or Benadryl, to help prevent side effects. These extra medicines can pass into your breast milk for a short time.

Dr. Madhavan suggests having a plan:

• Feed Before You Go: Breastfeed your baby right before you leave for your appointment.
• Use Saved Milk or Formula After: For the next few hours after your treatment, if you have a supply of pumped breast milk, use that or formula to feed your baby.
  
  

"Having a plan like this gives you peace of mind on treatment days," says Dr. Madhavan. "Your doctor can tell you exactly how long you should wait before breastfeeding again. It’s a simple way to make sure your baby stays safe while you get the care you need."

Next Steps & Resources: 

• Meet our sources: Joseph Canterino, M.D. & Maya Madhavan, M.D.
• To make an appointment with a doctor near you, call 800-822-8905 or visit our website.
• Learn more about our multiple sclerosis care services.

The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.