Will pregnancy affect my asthma?

Pregnancy can affect your asthma in different ways. Roughly 1 in 3 people with asthma find their asthma gets worse during pregnancy. However, about 1 in 3 people find their asthma improves during pregnancy.

Many people who are pregnant feel short of breath at times, even if they don’t have asthma.

Hormonal changes that occur during pregnancy can make it feel harder to breathe. As your baby grows and your uterus gets bigger, there is also less space for your lungs to expand.

When you're pregnant, you are more likely to catch a virus, such as a cold or the flu. This can make your asthma symptoms worse.

Your asthma will usually return to normal about 3 months after your baby is born, even if it gets worse while you are pregnant.

Will having asthma affect my baby?

If your asthma is well-controlled, it won't affect your baby.

Poorly-controlled asthma can cause complications for you and your baby.

If you have asthma symptoms and have trouble breathing, you won't get enough oxygen into your lungs. If you are pregnant, your baby won't get enough oxygen either. This can increase your baby’s chance of:

• having abnormal growth and development
• having a lower than average birthweight
• being born prematurely (early)
• having a birth difference (congenital disorder)

Poorly-controlled asthma can also cause pregnancy complications, such as:

• pre-eclampsia (high blood pressure during pregnancy)
• problems with your placenta
• abnormal bleeding
• gestational diabetes (diabetes that develops during pregnancy)

You might feel concerned about taking medicines during pregnancy — but remember, it's safer for both you and your baby when your asthma is well-managed.

How do I manage my asthma during pregnancy?

It's important to notice if your asthma is worsening. If you think your asthma is getting worse talk to your doctor about a new asthma action plan.

This table can help you understand the signs of poor asthma control.

Routine management

It's important to keep taking your usual asthma medicines while you are pregnant. Most asthma medicines are considered safe to take during pregnancy. Not taking your asthma medication during pregnancy may lead to worse asthma symptoms, which can cause complications for you and your baby.

Talk to your doctor or pharmacist to find out more about your asthma medicines.

Continue to follow your asthma action plan. See your doctor if your asthma symptoms change. Your doctor can adjust your asthma action plan to help manage your symptoms.

Stay up to date with your vaccinations during pregnancy, to help protect yourself from illness. Asthma can increase your risk of having complications from some illnesses. If you are pregnant or planning to become pregnant, ask your doctor which vaccinations you may need.

Asthma attacks

If you have an asthma attack, also known as a flare-up, it's important to treat it straight away. Take your reliever medicine according to the instructions in your asthma action plan. See your doctor straight away or go to your local hospital emergency department if your symptoms do not improve after two doses of your reliever medicine.

You might need to take corticosteroids, such as prednisolone. These are safe to take during pregnancy.

When should I see my doctor?

See your doctor every 4 to 6 weeks during pregnancy, to make sure your asthma is well-managed.

If your breathing is getting worse during pregnancy, see your doctor as soon as possible. They can help you work out whether your symptoms are a normal part of pregnancy or related to your asthma.

Your asthma might be getting worse if:

• your breathing makes it hard to do your usual activities
• asthma symptoms wake you up at night
• your asthma symptoms mean you need to take a reliever medicine more than twice a week

If you have had an asthma attack, see your doctor after you have recovered. They can adjust your asthma action plan to help prevent future asthma flare-ups.

Will having asthma affect how I give birth?

Having asthma does not usually affect how you give birth.

Asthma symptoms that occur during labour are usually managed according to your usual asthma action plan. Bring your asthma medicines with you to the hospital or birthing centre when you go into labour. You should also bring a copy of your asthma action plan.

Asthma flare-ups during labour are rare.

Can I breastfeed if I am taking asthma medicine?

You can safely breastfeed your baby while taking most asthma medicines. After taking asthma medicine there is no need to wait before breastfeeding your baby.

It's safe to take a short course of steroid tablets while you're breastfeeding. You might be advised to wait 4 hours after taking the medicine before breastfeeding. If you have been prescribed steroid tablets, ask your doctor or pharmacist for advice.

Some asthma medicines, such as montelukast, may not be recommended while breastfeeding. Talk to your doctor or pharmacist to find out more about breastfeeding safely when taking your asthma medicine.

Will my baby have asthma?

Asthma tends to run in families and can be caused by your genes. This means your baby is more likely to have asthma if you or other close family members have asthma.

There are things you can do to lower your baby's chance of developing asthma. You can:

• quit smoking or vaping when you are pregnant
• avoid being around other people who are smoking when you are pregnant
• breastfeed your baby

Resources and support

Your doctor or midwife can answer your questions about pregnancy and asthma. They can also make sure that your asthma action plan is up to date.

Visit Asthma Australia or call 1800 278 462 to find out more about pregnancy and asthma.

You can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.

Languages other than English

The National Asthma Council has information in other languages.

Information for Aboriginal and/or Torres Strait Islander peoples

The Asthma in Pregnancy Toolkit has information for Aboriginal and/or Torres Strait Islander peoples, as well as culturally safe models of care during pregnancy.