Asthma and Pregnancy: What You Need to Know

The single most important thing: keep taking your preventer inhaler

If you are pregnant and you have asthma, the most useful thing you can do for yourself and your baby is to keep your asthma well controlled. That means continuing with your preventer inhaler every day, exactly as prescribed, even if you feel completely well. Stopping it is the biggest risk you could take.

It is understandable to worry about medicines in pregnancy. But the evidence is reassuring: the inhalers used to treat asthma in the UK have been used in pregnancy for decades, and the small doses involved mean very little reaches your baby. What does reach your baby is your oxygen. When your asthma is poorly controlled, your blood oxygen levels can drop, and that affects the oxygen supply to your baby too.

If you have stopped your preventer since finding out you were pregnant, tell your GP, asthma nurse or midwife today. You can safely restart it.

Why good control matters for you and your baby

Asthma affects roughly one in ten pregnancies in the UK. When it is well managed, the risks are low and most women have a straightforward pregnancy. When it is not, the risks rise for both of you.

• Poorly controlled asthma is linked to a higher chance of pre-eclampsia, gestational diabetes and needing a caesarean birth.
• It increases the risk of your baby being born early or smaller than expected.
• Uncontrolled asthma makes asthma attacks more likely, and an attack in pregnancy is a medical emergency that needs treating straight away.

The reassuring part is that all of these risks are reducible. Good day-to-day control, a written asthma action plan, and prompt treatment when symptoms flare are what protect you both.

Which asthma medicines are safe in pregnancy?

Your usual routine treatment is almost certainly fine to continue.

• Preventer inhalers (often brown, purple or red) — keep using them daily. This is the foundation of safe care.
• Reliever inhalers (usually blue) — carry yours at all times and use it when you need it. Needing it is not a sign of failure; it is a sign you may need your preventer reviewed.
• Steroid tablets — if you have an asthma attack, you may be offered a short course. Do not delay or refuse this. Untreated asthma is far more dangerous than the treatment.
• Other treatments, including add-on tablets or specialist injections, should be discussed individually with your asthma team rather than stopped on your own.

Ask about any medicine you are unsure of rather than simply going without. You should also be offered the seasonal flu jab, which is free in pregnancy and strongly recommended if you have asthma.

Your asthma reviews and maternity care

Asthma often changes during pregnancy. Roughly a third of women find it improves, a third find it stays the same, and a third find it gets worse — and you cannot predict which group you will be in.

Book an asthma review early in pregnancy if you have not had one recently. Ask for:

• A check of your inhaler technique — it is easy to slip into habits that mean less medicine reaches your lungs.
• An up-to-date written asthma action plan, so you know exactly what to do if symptoms worsen.
• A peak flow meter and advice on your personal best reading, so you can spot changes early.

Tell your midwife at your booking appointment that you have asthma, and mention it at every subsequent visit. Your midwife and GP or asthma nurse should be working together, and you are entitled to be part of that conversation.

Practical day-to-day self-management

Small, consistent habits make a real difference.

• Avoid your triggers. Keep your home as dust-free as you reasonably can, ventilate when cooking, and stay indoors on high pollen days if that is a trigger for you.
• Watch out for reflux. Heartburn is common in later pregnancy and can make asthma symptoms worse. Mention it — it is treatable.
• Stay active. Gentle exercise is good for you and your baby. Use your reliever beforehand if your action plan says to.
• Do not smoke, and keep your home smoke-free. Ask for support to quit; it is available and it works.
• Keep your weight gain within the range your midwife advises, as extra weight can make breathlessness feel worse.

Get urgent help if your reliever is not lasting four hours, if you are too breathless to speak in full sentences, or if you feel your symptoms are worsening quickly. Do not wait for your next appointment.

Labour, birth and the weeks afterwards

Bring your inhalers to hospital and tell the staff you have asthma when you arrive. Most women with well-controlled asthma can have the birth they planned, including a home birth if that is your preference and your pregnancy is low risk.

After your baby is born, asthma usually returns to its pre-pregnancy pattern. Keep taking your inhalers, especially if you are breastfeeding — the amount passed to your baby is tiny, and breastfeeding protects both of you.

Ask for a review around six weeks after the birth, and again before you return to work. If you have any concerns at any point, raise them early. Well-managed asthma means you can focus on your pregnancy and your new baby, which is exactly where your attention should be.