Asthma in Pregnancy UK: Is It Safe to Use Your Inhaler?
▶ Asthma pregnancy UK
Asthma affects 1 in 10 pregnant women in the UK. Salbutamol (Ventolin) and ICS preventer inhalers are safe in pregnancy and should be continued — poorly controlled asthma poses far greater risks to mother and baby (premature birth, low birth weight) than standard inhaler use. Never stop asthma inhalers in pregnancy without medical guidance.
Asthma affects approximately 1 in 10 pregnant women in the UK, making it the most common respiratory condition in pregnancy. The key message of this guide — supported by every major clinical guideline — is: the risks of poorly controlled asthma during pregnancy are significantly greater than the risks of any recommended asthma medication. Do not stop your inhalers in pregnancy. Both your reliever and preventer are safe, necessary, and should be continued.
For your reliever inhaler: see Understanding and Using Your Ventolin Inhaler. For preventer inhalers: see Preventer Inhalers for Asthma.
Do not stop your asthma inhalers in pregnancy. Poorly controlled asthma carries serious risks for both you and your baby. All standard asthma inhalers (salbutamol reliever and ICS preventer) are considered safe in pregnancy. Always discuss any medication concerns with your GP or midwife — do not stop treatment without clinical guidance.
Already Prescribed? Order Your Inhaler Online
GPhC-registered pharmacist independent prescribers · Reliever and preventer inhalers · Note: Pregnant women should seek in-person GP or midwife review for any asthma changes.
Start Consultation →Does Pregnancy Affect Asthma?
Pregnancy affects asthma differently in different women. The widely-cited rule of thirds is a reasonable approximation of the population-level pattern:
- ~1/3 improve — often linked to elevated progesterone (a bronchodilator), reduced allergen exposure from lifestyle changes, or simply natural variation
- ~1/3 stay the same — asthma control is unchanged throughout pregnancy
- ~1/3 worsen — most commonly in the second trimester (around weeks 24–36)
Asthma severity in previous pregnancies is a reasonable predictor of what to expect in subsequent ones. Notably, asthma attacks are least common in the final four weeks of pregnancy — possibly due to elevated cortisol levels near term.
GORD and asthma in pregnancy: Gastro-oesophageal reflux disease (GORD) is common in pregnancy and can significantly worsen asthma symptoms. If your asthma seems harder to control in pregnancy, mention any heartburn or regurgitation symptoms to your GP or midwife — treating GORD may improve asthma control.
Risks of Poorly Controlled Asthma in Pregnancy
The evidence is clear: poorly controlled asthma carries significant risks for both mother and baby. These risks are consistently greater than the risks of any recommended asthma medication:
| Risk | Associated with |
|---|---|
| Premature birth (before 37 weeks) | Poorly controlled asthma; severe attacks |
| Low birth weight | Chronic hypoxaemia from poorly managed asthma |
| Pre-eclampsia | Increased risk in women with poorly controlled asthma |
| Increased caesarean section rate | Uncontrolled or severe asthma requiring emergency management |
| Neonatal hypoxia | Severe asthma attacks causing maternal oxygen desaturation |
A baby in utero depends entirely on maternal oxygenation. A severe asthma attack that reduces maternal oxygen saturation reduces foetal oxygen supply. This is why treating asthma attacks promptly in pregnancy — and preventing them with daily preventer therapy — is more important than in non-pregnant women.
Is It Safe to Use a Reliever Inhaler During Pregnancy?
Yes. Salbutamol (Ventolin, Salamol) is safe throughout pregnancy and is the recommended reliever inhaler for pregnant women with asthma. It is listed as appropriate for use in pregnancy by:
- NICE NG245 (Asthma: diagnosis, monitoring and chronic asthma management)
- BTS/SIGN British Guideline on the Management of Asthma
- Royal College of Obstetricians and Gynaecologists
- The UK Medicines in Pregnancy teratology service (UKTIS)
Salbutamol has been used by millions of pregnant women worldwide. The drug reaches the airways in very small quantities; systemic absorption at standard doses is minimal. If you need your reliever inhaler, use it — uncontrolled breathlessness or a severe attack is far more dangerous than the inhaler.
Is It Safe to Use a Preventer Inhaler During Pregnancy?
Yes. Inhaled corticosteroid preventers should be continued throughout pregnancy. The amount of ICS entering the bloodstream from standard inhaled doses is very small — significantly less than oral steroids and clinically insignificant at standard doses. NICE and BTS both explicitly recommend continuing preventer inhalers throughout pregnancy. Stopping your preventer:
- Allows airway inflammation to rebuild over weeks
- Dramatically increases the risk of severe attacks
- Reduces your ability to protect your baby from the effects of severe bronchoconstriction
For information on your preventer inhaler, see: Preventer Inhalers for Asthma.
Combination Inhalers and Pregnancy
ICS+LABA combination inhalers (Seretide, Symbicort, Fostair) are generally considered appropriate to continue in pregnancy if they are providing good asthma control. The safety data for salmeterol (in Seretide) and formoterol (in Symbicort, Fostair) in pregnancy is reassuring. Any change to your combination inhaler therapy in pregnancy should be discussed with your prescriber.
Do not change your inhaler regimen in pregnancy without prescriber guidance. If you are concerned about any of your medications in pregnancy, contact your GP or midwife. Access Doctor’s online service is not appropriate for managing asthma changes during pregnancy — in-person review is recommended.
Asthma Attacks During Pregnancy: What to Do
Manage an asthma attack in pregnancy exactly as you would outside pregnancy. Use your reliever inhaler (up to 10 puffs via spacer), sit upright, and call 999 if symptoms do not improve after 15 minutes, or immediately if symptoms are severe. In a severe attack in pregnancy, call 999 and tell them you are pregnant — this is important for the emergency response team. Do not delay emergency treatment due to concerns about medication safety.
Monitoring Your Asthma in Pregnancy
- Inform your midwife and obstetrician of your asthma diagnosis at your booking appointment
- Continue attending your annual asthma review with your GP or asthma nurse
- Use a peak flow meter daily if your asthma has been poorly controlled or if instructed to by your asthma nurse
- Keep your written asthma action plan up to date
- Contact your GP if your reliever use is increasing or your asthma is deteriorating — prompt treatment prevents severe attacks
- Flu vaccination is strongly recommended in pregnancy and is safe
Asthma and Breastfeeding
Standard asthma inhalers — reliever (salbutamol) and preventer (ICS) — are compatible with breastfeeding. Only very small quantities reach breast milk from inhaled doses. Continue your inhalers while breastfeeding. If you have any concerns, discuss with your GP, midwife, or pharmacist.
Repeat Asthma Inhalers — Online (non-pregnant patients)
GPhC-registered pharmacy #9011198 · Pharmacist independent prescribers. Note: Pregnant women should seek in-person review for any asthma changes.
Start Consultation →Frequently Asked Questions
Is it safe to use a Ventolin inhaler during pregnancy?
Yes. Salbutamol (Ventolin) is considered safe throughout pregnancy. It is the recommended reliever inhaler for pregnant women with asthma and has been used by millions of pregnant women worldwide with no evidence of harm to the developing baby. The Royal College of Obstetricians and Gynaecologists, NICE, and the British Thoracic Society all confirm that the benefits of using salbutamol during pregnancy far outweigh any theoretical risks. Poorly controlled asthma poses significantly greater risks to both mother and baby than inhaler use.
Is it safe to use a preventer inhaler during pregnancy?
Yes. Inhaled corticosteroid (ICS) preventer inhalers are considered safe during pregnancy and should be continued. The amount of ICS reaching the bloodstream from standard doses is very small. Stopping your preventer increases the risk of asthma attacks, which carry serious risks in pregnancy including reduced oxygen supply to the baby. NICE and the BTS specifically recommend that preventer inhalers should be continued throughout pregnancy.
Does pregnancy make asthma better or worse?
Both changes are possible — the rule of thirds applies: approximately one-third of women find their asthma improves during pregnancy, one-third find it stays the same, and one-third find it worsens. Asthma is most likely to worsen during the second trimester. The good news is that asthma tends to improve in the final four weeks of pregnancy in most women. Hormonal changes, including elevated progesterone, may contribute to either improvement or worsening depending on the individual.
What are the risks of poorly controlled asthma in pregnancy?
Poorly controlled asthma during pregnancy is associated with significant risks for both mother and baby, including: premature birth, low birth weight, pre-eclampsia, gestational diabetes, increased risk of caesarean section, and for the baby, reduced oxygen supply during severe attacks. These risks are all greater than any risks from taking NICE-recommended asthma medications. The key message: poorly controlled asthma is more dangerous than well-controlled asthma managed with inhalers.
Which asthma medications should be avoided in pregnancy?
Most asthma medications are safe in pregnancy and should be continued. Oral corticosteroids (steroid tablets) for severe attacks carry a slightly increased risk of cleft palate if used in the first trimester, but this risk is outweighed by the risk of a severe, untreated attack. Discuss any concerns about your specific medications with your GP, midwife, or obstetrician. Do not stop any asthma medication in pregnancy without medical guidance.
Can asthma affect labour and delivery?
Asthma attacks during labour are uncommon — possibly because of elevated cortisol levels during labour. However, for women with poorly controlled asthma, it is important to have your reliever inhaler accessible throughout labour. Epidural anaesthesia and nitrous oxide (gas and air) are safe for women with asthma. Aspirin-based pain relief should be avoided in aspirin-sensitive asthma. Prostaglandin F2α (used to induce labour in some cases) can trigger bronchoconstriction in some women with asthma — inform your obstetric team of your asthma diagnosis.
References
- NICE. Asthma: diagnosis, monitoring and chronic asthma management (NG245). 2024. nice.org.uk/guidance/ng245
- NHS. Asthma. nhs.uk/conditions/asthma
- Asthma + Lung UK. Asthma facts and statistics. asthma.org.uk
- BTS/SIGN. British Guideline on the Management of Asthma (SIGN 158). 2023. sign.ac.uk
- MHRA. Salbutamol (Ventolin Evohaler) summary of product characteristics. medicines.org.uk/emc
- GPhC. Standards for registered pharmacies. pharmacyregulation.org
Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Asthma inhalers are prescription-only medicines — a clinical consultation is required before they can be dispensed. If you are experiencing a severe asthma attack, call 999 immediately. Always follow the guidance of your prescriber or asthma nurse. In a medical emergency, call 999.