Asthma and Pregnancy: What to Know

If you’re pregnant, you’ll want to work closely with your doctor and make sure to manage your symptoms. As long as it’s under control, your pregnancy is likely to be just like anyone else’s.

How Might Pregnancy Affect My Asthma?

A lot of hormone changes happen during pregnancy, and some of them can affect your lungs.

One-third of women find that their asthma improves during their pregnancy. One-third don’t notice any difference, and the final third of women feel that their asthma symptoms become harder to control. This is more likely to happen if your asthma is severe. If so, you may notice that your asthma flares up the most during weeks 29 through 36 of your pregnancy.

Can Asthma Affect My Baby During Pregnancy?

Severe asthma or symptoms that aren’t well-controlled can cause a number of problems:

Your baby depends on a constant supply of oxygen in your blood to stay healthy and develop the way she should. If your asthma symptoms aren’t controlled, your blood may not have enough oxygen to support your baby. This can lead to a low birth weight (less than 5.5 pounds). But that’s not likely to happen. Most women who control their asthma during pregnancy deliver healthy babies.

Are Asthma Medicines Safe for Me to Take?

Experts believe that fast-acting inhalers and inhaled corticosteroids are safe to take when you’re pregnant. These medicines go right into your lungs. Very little is absorbed into your bloodstream where it could reach your baby.

Doctors often don’t prescribe asthma pills and liquids taken by mouth for pregnant women unless nothing else works. If this is the case, your doctor should prescribe an older drug that’s been well-studied and shown to cause little risk to your baby. You’ll want to avoid taking any new medicines whose long-term effects aren’t known yet.

Although birth defects caused by asthma medicines are rare, your doctor may still try to cut back on your dosage during your first trimester.

You should feel free to ask your doctor any questions, just as you would for any other concerns you have. Keep in mind that letting your asthma symptoms go untreated poses a greater risk to your baby than any treatment your doctor may prescribe.


Is My Baby More Likely to Get Asthma If I Have It?

Many women with asthma give birth to healthy babies. Most cases of asthma are mild, not severe, and can be safely managed with medicine.

It’s unclear whether breastfeeding can lower the chance that your baby will develop asthma. So far, studies only show that breastfed babies wheeze less during their first 2 years of life.

What Else Can I Do to Control My Asthma?

To keep both yourself and your baby healthy, you can:

  • Know your asthma triggers and avoid them. These vary from one person to the next, but they often include cold and flu viruses, tobacco smoke, and allergens like mold, pollen, and dust mites. Staying away from your triggers may mean that you can use less medicine.
  • Follow your doctor’s orders. Take your medicines as prescribed and don’t stop them without first checking with your doctor.
  • Exercise carefully. Ask your doctor about safe ways you can stay active, especially if physical activity has caused you to have an asthma attack in the past.
  • Be aware of warning signs. If your treatment stops working, you have trouble breathing, or you notice that your baby isn’t moving or kicking around like usual, call your doctor right away.
WebMD Medical Reference Reviewed by Kecia Gaither, MD, MPH on May 05, 2017



March of Dimes: “Asthma During Pregnancy.” “Fact Sheet: Asthma.”

UpToDate: “Patient education: Asthma and pregnancy (Beyond the Basics.)”

Mayo Clinic: “Pregnancy and Asthma: Managing Your Symptoms.”

Johns Hopkins Medicine: “Asthma and Pregnancy.”

American Academy of Allergy Asthma & Immunology: “Asthma, Allergies, and Pregnancy.”

American College of Allergy, Asthma & Immunology: “Pregnancy and Asthma.”

University of Iowa Stead Family Children’s Hospital: “Asthma and Pregnancy (Effects on the Mother and Baby.)”

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