Skip navigation links
Home Allergy Management
Success Stories
Trigger Avoidance
Find an Allergist

Managing Asthma and Allergies During Pregnancy

If you have asthma or allergies and are pregnant or considering becoming pregnant, this important information will promote a safe pregnancy and delivery, and a healthy baby.

Asthma affects almost 7 percent of pregnant women and can cause serious complications for both mother and child if not controlled properly during pregnancy. Complications for the expectant mother may include high blood pressure and preeclampsia, a disorder that occurs when high blood pressure is accompanied by fluid retention and leaking of protein into the mother's urine, potentially damaging her kidneys, brain, liver and eyes. If the condition results in seizures, it can be deadly for both the mother and baby. Other complications for the baby include an increased risk of premature birth, low birth weight, slow growth and stillbirth.

The good news is that asthma and allergies can be controlled, and when they are, the risks to mother and baby are extremely low.

How will my pregnancy affect the severity of my asthma?

If you have asthma, you probably feel a tightness in your chest and may experience wheezing, shortness of breath and/or coughing. These symptoms are caused by muscle spasms that constrict the flow of air to the lungs. The linings of the airways become inflamed and swollen, and may be clogged by excess mucus. Asthma may be triggered by allergens, including pollen, mold, animal dander, house dust mites and cockroaches; other environmental factors; exercise; infections and stress.

Your asthma may become worse during your pregnancy, especially if your condition is considered severe. On the other hand, about a third of asthma patients improve during pregnancy, especially if their disease was mild before they became pregnant. Another third experience no change. If your asthma or asthma attacks become worse, it will most likely occur during 24 to 36 weeks of your pregnancy. Only about 1 in 10 women with asthma have symptoms during delivery.

The hormonal changes that occur during your pregnancy may affect your nose, sinuses and lungs, causing congestion and shortness of breath. Your doctor will help you determine if these symptoms, which may be confused with your asthma or may trigger your asthma, are actually caused by the disease.

If you've been pregnant before, you can probably expect your asthma to behave the same way in subsequent pregnancies. Within three months of your baby's birth, your asthma probably will return to the way it was before you became pregnant.

How will I know if my asthma is affecting my baby?

Depending on your age and any other risk factors, your doctor may conduct several tests throughout your pregnancy to monitor and evaluate your asthma and the effect it has on you and your baby's health.

Sonography or ultrasound can be performed during the first trimester to confirm the accuracy of your estimated due date. The test may be repeated later if slow growth in the baby is suspected.

Electronic heart rate monitoring, called "non-stress testing" or "contraction-stress testing," and ultrasound may be used in the third trimester to assess your baby's well-being. If you are experiencing significant asthma symptoms during this trimester, the frequency of the monitoring may be increased. All asthma patients should record their baby's activity and kick counts daily to help monitor the baby, according to their doctor's instructions.

If you experience a severe asthma attack during your pregnancy in which your symptoms do not quickly improve, there is a risk you may experience hypoxemia, or a low oxygen state. This is an important time to assess your baby's health, and continuous electronic fetal heart rate monitoring may be necessary, along with measurements of your lung function.

Fortunately, the majority of asthma patients do well during labor and delivery, although careful fetal monitoring remains very important. If you are a low-risk patient with well-controlled asthma, a fetal assessment can be accomplished by 20 minutes of electronic monitoring shortly after you are admitted to the hospital.

If you have severe asthma or other risk factors, more intensive fetal monitoring and observation is recommended.

What steps can I take to control my asthma and allergies while I'm pregnant?
Asthma and allergies are often connected. Most asthma patients are allergic to one or more allergens such as pollens, molds, pet dander, house dust mites and cockroaches. These allergens may trigger your asthma symptoms or make existing symptoms worse.

Other non-allergic substances also may worsen your asthma and allergies. These include tobacco smoke, paint and chemical fumes, strong odors, environmental pollutants (including ozone and smog) and drugs, such as aspirin or beta-blockers (used to treat high blood pressure, migraine headaches and heart disorders).

By avoiding specific triggers, you can decrease the frequency and intensity of your asthma and allergy symptoms. If a patient tests allergic to a specific trigger, allergists-immunologists recommend the following avoidance steps:

  • Remove allergy-causing pets from the house.
  • Seal pillows, mattresses and box springs in special dust mite-proof casings (your allergist should be able to give you information regarding comfortable cases).
  • Wash bedding weekly in 130 degrees F water (comforters
    may be dry-cleaned periodically) to kill dust mites.* Keep home humidity under 50 percent to control dust
    mite and mold growth.
  • Use filtering vacuums or "filter vacuum bags" to control airborne dust when cleaning.
  • Close windows, use air-conditioning and avoid outdoor activity between 5 a.m. and 10 a.m., when pollen and pollution are at their highest.

Can I use my asthma and allergy medications while I'm pregnant and nursing?

Today there are many excellent medications for treating asthma and allergies. Although no medication can be proven entirely safe for use during pregnancy, you and your doctor will work together to develop a treatment plan that carefully balances medication use and symptom control, and assures that the potential benefits of the medication outweigh the potential risks of the medication and of uncontrolled asthma.

Since the symptoms associated with asthma and allergies can vary from day to day, month to month, or season to season, regardless of pregnancy, your treatment plan will be based on the severity of your disease and previous experience using specific medications during pregnancy. It's important to remember that the use of medication should not replace the avoidance of the allergens or irritants that trigger your asthma and allergies, since avoidance can potentially reduce your need for medication.
Medications used during pregnancy are usually selected based on the following criteria:

  • Inhaled medications are generally preferred because they have a more localized effect with only small amounts entering the bloodstream.
  • Time-tested older medications are preferred since there is more experience with their use during pregnancy.
  • Medication use is limited in the first trimester as much as possible when the baby is developing the most, although birth defects due to medications are rare (no more than 1 percent of all birth defects are attributable to all medications).

In general, the same medications used during pregnancy are appropriate during labor and delivery and when nursing. To obtain the lowest concentration of a medication in breast milk, it is recommended that you take the medication 15 minutes after nursing or three to four hours before your baby's next feeding.

Can I receive allergy shots or a flu shot when I'm pregnant?

Allergy shots (immunotherapy) are often effective if you continue to experience symptoms despite allergen avoidance and proper medication. If you currently are receiving immunotherapy for the treatment of your asthma and/or allergies, it can be carefully continued during pregnancy if you benefit from the treatment and do not experience any adverse reactions. It is not recommended, however, that immunotherapy be initiated during a pregnancy.

If you have moderate or severe asthma, an influenza (flu) vaccine is recommended. There is no evidence of risk for you or your baby.


Proper control and treatment of your asthma and allergies, including regular visits with your doctor to evaluate and monitor your symptoms and medication, will help promote a healthy pregnancy and baby.

Remember that the potential risks of asthma medications are lower than the risks of uncontrolled asthma, which can be harmful to you and your baby. The use of any asthma or allergy medication needs to be discussed with your doctor, ideally before pregnancy. Notify your doctor immediately if you are planning to discontinue birth control or as soon as you know you are pregnant.


Find a Free Asthma Screening Near You

Free asthma and nasal allergy screenings, performed by allergists, are held at more than 200 locations across the country. Find one near you today!

Learn More »

Find an Allergist

Allergists are specialists at treating both allergies and asthma. They can explain how your allergies can affect your asthma and steps you need to take to keep both conditions under control. Find an allergist in your zip code and find relief.

Learn More »

Allergy and Asthma Success Stories

Read stories of people just like you. Learn how they found relief from their allergy and asthma symptoms by visiting an allergist.

Learn More »