This sheet talks about exposure to inhaled corticosteroids in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.

What are inhaled corticosteroids?

Inhaled corticosteroids (ICSs) are medications to prevent and control the symptoms of asthma. ICSs are taken using an inhaler, pump, or nebulizer. ICSs can have fewer side effects than corticosteroids pills since most of the inhaled medication goes directly to the lungs instead of traveling throughout the body.

ICSs help control the swelling of the airways in the lungs and reduce mucus production so that asthma attacks are less likely. ICSs are not effective in stopping immediate symptoms when you are having an asthma attack. Some examples of ICSs are beclomethasone dipropionate (Qvar®), budesonide (Pulmicort®), fluticasone propionate (Flovent®), mometasone furoate (Asmanex®), or triamcinolone acetonide (Azmacort®).

This fact sheet will focus on corticosteroids that are inhaled (breathed into lungs), and not corticosteroids taken in other ways (such as pills). For more information about corticosteroids taken in a pill form, see the MotherToBaby fact sheet on prednisone/prednisolone at or the MotherToBaby fact sheet on topical corticosteroids at

I just found out I am pregnant. Should I stop taking my ICS?

Talk with your healthcare provider before making any changes to this medication. Untreated asthma can cause problems for a pregnancy (see the MotherToBaby fact sheet on asthma at ICSs are considered preferred asthma treatments during pregnancy because they usually control asthma well. They are absorbed into the body in lower amounts compared to pill / tablet forms of the medication. It is unknown how much, if any, of the medication reaches the developing baby. However, research suggests that the amount is likely small.*

It is important to control your asthma symptoms with medicine that works for you. If you are taking an ICS that is working for you, it is not recommended that you switch medications during pregnancy without talking to your healthcare provider.

Can taking ICSs during my pregnancy cause a birth defect?

In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. High doses of ICSs (doses that could be closer to the doses found in corticosteroid pills) have not been well studied during pregnancy. However, the studies that have been done on ICSs have found no overall increased chance for birth defects.

Can taking ICSs during pregnancy cause other pregnancy complications?

ICSs are not associated with pregnancy complications. However, untreated asthma can cause low birth weight and other pregnancy complications. It is important to work with your healthcare team to make sure your asthma is well-controlled during pregnancy.

Can I take ICSs while breastfeeding?

Most ICSs have not been studied during breastfeeding. However, the amount of medication that would be in the breast milk following inhalation is likely too small to cause problems for a breastfeeding infant. Talk to your healthcare provider about all of your breastfeeding questions.

What if the father of the baby takes an ICS?

There is no evidence that ICSs taken by men would affect their sperm or in some way be harmful to a pregnancy. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet on paternal exposures at

MotherToBaby is currently conducting a study looking at asthma and the medications used to treat asthma in pregnancy. If you are interested in taking part in this study, please call 1-877-311-8972 or sign up at

* Section Updated May 2020

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