Asthma during Pregnancy

Every pregnancy is a precious and unique experience that many women cherish. However, for women with asthma, with every flutter and kick from the baby, the anticipation always comes alongside the persistent concern of how asthma would affect their pregnancy. It does not have to be this way. With the right care and support, most women with asthma will have a safe pregnancy and deliver a healthy baby.  

What would pregnancy do to my asthma control? 

Truth is, the changes to asthma control usually vary from one pregnant woman to another and it is rather difficult to predict the course of asthma control throughout the pregnancy too. Available statistics show that approximately one-third of pregnant women with asthma will experience an exacerbation of their asthma symptoms. Another one-third will maintain a stable condition, while the remaining one-third will observe an improvement in their asthma symptoms. Despite the unpredictability, the general trends found by various studies are such that: 

1. Women with severe uncontrolled asthma before pregnancy are more likely to experience exacerbation while women with mild and well-controlled asthma before pregnancy usually remain stable or experience improvement. 

2. Most who experience a change in asthma control will return to pre-pregnancy condition within 3 months post-labour. 

3. Whether your asthma control worsens or improves in your current pregnancy, the same trend will very likely be observed in your successive pregnancies. Hence, if this is not your first pregnancy, you might know better than the last time what you can expect! 

With that being said, it is wise to review and monitor asthma control together with your primary care doctor and specialists. 

What would my asthma do to my pregnancy and my baby? 

The rule of thumb is complications mostly happen if your asthma is poorly controlled. In fact, well-controlled asthma has been found to decrease the risks of birth defects and birth and delivery complications while a poorly controlled asthma could lead to: 

1. Small increased risk of preterm birth 

2. Increased risk of pre-eclampsia (a pregnancy disorder where there is high blood pressure and protein in urine)

3. Increased risk of the infant with low birth weight (defined by infant weighing less than 2.5kg) 

4. Decreased oxygen content in foetal blood hence negatively impacts foetal growth and survival 

5. Increased risk of children developing asthma later in life 

As you are now aware, achieving good asthma control during pregnancy is crucial for both you and your baby.  

Taking your prescribed medications

Good asthma control can be achieved by several ways, some as easy as adhering to your medications as prescribed. While most asthma medications are safe to be used during pregnancy and will not cause harm to your foetus, some medicines are considered safer than the others given that we have more safety data of their uses. We will discuss  some of the most commonly-used asthma medications and their general safety information but bear in mind that this does not substitute for professional medical advice. 

1. Short-acting beta-2 agonist (SABA)

This class of medication is frequently known as a “reliever” and is used only during acute asthma attacks. The US FDA classifies it as Category A of pregnancy medication, suggesting that there is sufficient data to prove that its use is not found to be associated with an increased risk of harmful effects on the foetus. 

Examples: Ventolin, Asthalin 

2. Inhaled corticosteroids 

Inhaled corticosteroids (ICS) are usually used as a preventative measure and it is known as “preventer”. ICS are the most effective long-term controller medication for asthma. They are generally considered safe during pregnancy, as they are mainly absorbed into the lungs and have very little systemic absorption. 

Examples: Pulmicort, Flixotide 

3. Long-acting beta-2 agonists (LABA)

LABAs are usually only used in combination with inhaled corticosteroids (ICS) as part of an asthma management plan, and not as a standalone treatment. They are not typically the first-line options for pregnant women with asthma but may be considered by doctors if asthma remains poorly controlled with other medications. 

Examples: Symbicort 

4. Oral corticosteroids

Oral corticosteroids are used during severe asthma exacerbations. They are generally considered safe during pregnancy when used for short periods. 

Example: Prednisone

Current evidence also suggests that asthma medications can be safely used during breastfeeding. The key here is to always work closely together with your doctor to tailor the safest and most effective regimen for you. Always remember that asthma medication should never be stopped or changed without first consulting your healthcare provider as the benefits you can reap from a well-controlled asthma far outweighs the small or even insignificant risks of the asthma medications. 

Keeping out from the triggers 

Avoiding triggers is one of the most crucial components of asthma management. This is especially relevant for pregnant women who are more vulnerable to all the potential complications. Common asthma triggers are: 

1.  Allergens such as pollen, dust mites, and pet dander. Using an air filter can help with keeping these allergens out. For those who are allergic to pollen try to stay indoors when the pollen counts are high, for example in the morning. If dust-mites are a known trigger, wash your bedding regularly and use allergen-proof bed covers. 

2.  Irritants such as cigarette smoke, air pollutants, and strong odours. Avoid smoking yourself and any exposure to secondhand smoke. Stay indoors during periods of high air pollution. 

3. Respiratory infections like influenza and cold. Take preventive measures to avoid respiratory infections, such as frequent hand washing and avoiding contact with sick individuals. Get the flu vaccine as discussed below. 

Good asthma action plan and asthma education

Having an updated and well-thought-out asthma action plan is essential to achieve good asthma control for all asthma patients, including pregnant women. A good asthma action plan usually would include a list of triggers, signs and symptoms of asthma, instructions for taking medications including dosage and frequency at different stages of asthma, instructions to monitor asthmatic symptoms and peak flow readings, and when to seek medical help. A good asthma education serves the same functions. Hence, with a personalised asthma action plan in addition to good asthma education, you will be better able to manage your asthma during pregnancy. 

Asthma Malaysia has published an asthma action plan template that you may find useful. 

Taking the influenza and COVID-19 vaccine 

The flu and COVID-19 vaccine is safe and recommended for pregnant women with asthma at any stage of pregnancy, including during the first trimester. In fact, not only that getting the vaccines during pregnancy will protect you from risks of severe illness, it can also  provide protection for the developing foetus since the antibodies produced by the mother can cross the placenta and provide passive immunity to the baby.

All in All 

There are no reasons to let asthma hold you back from enjoying your pregnancy journey. With proper care and management, there is no limit to what pregnant women with asthma can do from preparing for the arrival of a new baby to enjoying time with family and friends. Here are our four key takeaways from the article for you- 

1. Your asthma control might worsen, improve, or remain the same during pregnancy, always work closely with your healthcare providers.

2. Achieving good asthma control is essential to prevent relevant complications and ensure a safe pregnancy and the delivery of a healthy baby.

3. Do not stop or change your asthma medications without first consulting your healthcare providers.

4. Other ways to achieve good asthma control include avoiding known triggers, having a well-designed asthma action plan alongside good asthma education, and taking the flu vaccine. 

This article is written by Ke Feng, Bpharm(Hons) DOC2US, 
reviewed by Dr. Lee Siew Ling, MD (DOC2US)

References 

1. National Asthma Council Australia. (2018e). Asthma in pregnant women. Retrieved from http://www.asthmahandbook.org.au/populations/pregnant-women
2. Asthma and Allergy Foundation of America. (2021). Asthma During Pregnancy. Retrieved from https://aafa.org/asthma/living-with-asthma/asthma-during-pregnancy/
3. Asthma Malaysia. (20). Using Asthma Action Plan. Retrieved from https://asthmamalaysia.org/publication-resources/
4. Asthma Malaysia. (20). Asthma and Pregnancy. Retrieved from https://asthmamalaysia.org/pregnancy/ 

Written by

Ke Feng, Bpharm(Hons) DOC2US