Asthma

Asthma During Pregnancy

Asthma is one of the most common medical problems that occurs during pregnancy. It can be potentially serious. Some studies have suggested that asthma complicates up to 7% of all pregnancies. About 30% of all women with asthma report their asthma  worsened while pregnant. But with the right treatment and care, you and your baby can have a good outcome. 

Does Asthma Cause Complications During Pregnancy?

Potential Complications

Pregnant women with asthma may have a bit greater risk of delivering early. Or the infant may have a low birth weight. High blood pressure and a related condition known as pre-eclampsia are also more common in pregnant women with more severe asthma.

It is not known if uncontrolled asthma causes these problems directly or if other reasons are to blame.

However, optimal control of asthma during pregnancy is the best way to cut the risk of these complications.

Changes in Asthma Severity

About one-third of pregnant women with asthma will see their asthma symptoms get worse. Another third will stay the same. The last third will see their asthma symptoms improve.

Most women with asthma whose symptoms changed in any way during pregnancy will return to their pre-pregnancy condition within three months after giving birth.

There is a tendency for women whose asthma symptoms increased or decreased during one pregnancy to experience the same thing in later pregnancies. It is difficult to predict how asthma will change during pregnancy.

Because of this uncertainty, asthma should be followed closely. This way, any change can be promptly matched with an appropriate change in treatment. This calls for good teamwork between the  obstetrician, primary care physician and asthma specialist.

How Does Uncontrolled Asthma Affect the Fetus? 

Uncontrolled asthma cuts  the oxygen content of the mother's blood. Since the fetus gets its oxygen from the mother's blood, this can lead to decreased oxygen in the fetal blood. The result may impair fetal growth and survival. The fetus requires a constant supply of oxygen for normal growth and development. There is evidence that adequate control of asthma during pregnancy reduces the chances of fetal or newborn death and improves fetal growth inside the uterus. There are no indications that a mother’s asthma contributes to either spontaneous abortion or congenital malformation of the fetus.

What Should I Do to Avoid Asthma Attacks During Pregnancy?

Avoid Your Asthma Triggers

Avoiding asthma triggers is always important, but is particularly important during pregnancy. Pregnant women with asthma should increase avoidance measures to gain greatest comfort with the least medication.

  • Stay away from people who are sick with respiratory infections.
  • Avoid allergens like dust mites, animal dander, pollen, mold and cockroach.

Stop Smoking Cigarettes/Tobacco

Giving up cigarette smoking is important for any pregnant woman. Smoking may worsen asthma and harms the health of the growing fetus as well.

Exercise

Regular exercise is important to health. Talk to your obstetrician for the best advice about exercising during pregnancy. Swimming is a particularly good exercise for people with asthma. Using quick-relief medicine 10 minutes before exercise may help you tolerate recommended exercise.

Are Asthma Medicines Safe to Use During Pregnancy?

Is It Safe to Use Asthma Inhalers or Corticosteroids While Pregnant

Ensuring asthma is well-controlled is key. It is recommended that mothers seek regular check-ups to ensure their asthma remains controlled. Working with an asthma provider is essential. The asthma regimen that is best suited for the mother is the best approach.

Some asthma medicines are considered "safer" during pregnancy because their risks appear to be less than the risks of uncontrolled asthma. These include:

  • short-acting  inhaled bronchodilators
  • anti-leukotriene agents like montelukast (Singulair) 
  • some inhaled corticosteroids, like budesonide

Based on the severity of the mother’s asthma, a doctor may consider switching her treatment to an inhaled corticosteroid alone.

Long-acting beta agonists (like Serevent, Symbicort and Advair) and theophylline are not considered first-line treatments for pregnant asthma patients. But doctors may consider them if the mother’s asthma is not adequately controlled by the above medicines.

If asthma is very severe, oral steroids such as prednisone, may be necessary for the health of the mother and baby.

Remember: It is better for mother and baby if the mother maintains asthma control (using any approved asthma drugs).

Are Allergy Shots Safe During Pregnancy?

Pregnant woman with asthma already receiving allergy shot therapy can usually continue if they are not having reactions.  

As an extra precaution, though, the allergist may cut the dosage of the allergy extract to reduce the chance that a severe allergic reaction occurs or at a minimum keep the dose the same but the dose should not be increased during pregnancy since that increases the chance of a reaction.

Are Flu Shots Safe to Receive During Pregnancy?

People with asthma should get flu shots. Pregnancy does not change that recommendation. In fact, influenza may be particularly severe in pregnant women.

Asthma Attacks During Labor

When asthma is under control, asthma attacks almost never occur during labor and delivery. Also, most women with well-controlled asthma are able to perform breathing techniques during their labor without difficulty.

Is It Safe to Breastfeed?

Doctors do not believe asthma medicines are harmful to a nursing baby when used in usual amounts. The transfer of asthma medicines into breast milk has not been fully studied.

When breastfeeding, drinking extra liquids to avoid dehydration is also important (as it is for all people with asthma). Discuss with your baby’s pediatrician.

Will I Pass On Asthma to My Baby?

Genetics plays a role in whether a baby will develop asthma. In other words, asthma tends to be more likely in a baby if their relatives have it. The environment also plays an important role.

Can I Do Anything to Prevent Asthma in My Baby?

One major prenatal risk factor for the development of asthma is maternal smoking. Giving up cigarette smoking is very important. Other prenatal factors that may influence the development of asthma are:

  • maternal stress
  • diet
  • vitamin D levels
  • antibiotic use
  • method of delivery

Talk to your doctors about identifying your risk factors and making safe changes in preparation for your new baby.


Medical Review November 2016.

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