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Pregnant smoking

Smoking during pregnancy can be dangerous for your baby. We look at the effects of smoking for expectant mums and how to stop smoking when pregnant.

For many women, smoking is a brief escape from the pressures of everyday life. But it’s important to remember that smoking is bad for your health, and smoking during pregnancy can harm your unborn baby.

It’s not easy to stop smoking, even when you’re expecting a baby. In fact, 10.5% of women were smokers at the time of birth in the UK in 2016/2017 (NHS Digital, 2017). But giving up is one of the most beneficial things a pregnant woman can do to improve her baby’s health, growth and development. Knowing the effects of smoking during pregnancy doesn’t necessarily make giving up any easier but there are plenty of sources of support available.

Many women feel more motivated to stop smoking when they become pregnant. And it’s worth boosting that motivation with any support you can get from family and friends, or from specialist health workers. If your partner smokes as well, it can really help to stop together.

Effects of smoking during pregnancy

Smoking even one cigarette exposes you and your baby to over 4,000 chemicals (NHS, 2017). It also means less oxygen and important nutrients can reach your baby through the placenta (RCOG, 2015).

If you smoke or are exposed to smoke, you’ll have increased levels of the poisonous gas carbon monoxide (CO) in your body than those who don’t. That means the amount of oxygen your baby receives will be restricted (RCOG, 2015). Because of this reduced oxygen supply, your baby’s heart is under strain every time you smoke (NHS, 2017).

The harmful effects of smoking while pregnant can include:

  • miscarriage
  • stillbirth (baby dying in womb or shortly after giving birth)
  • ectopic pregnancy (pregnancy growing outside of womb)
  • birth defects in babies
  • premature birth (before 37 weeks of pregnancy)
  • low birth weight
  • sudden infant death syndrome, or cot death
  • increased risk of infant mortality.

(NICE, 2010; RCOG, 2015; NHS, 2017)

Longer term effects of smoking while pregnant on children

Smoking while pregnant can have further-reaching implications for your child. Babies and children whose mothers smoke during pregnancy are at increased risk of:

  • asthma, chest and ear infections, pneumonia and bronchitis
  • psychological problems in childhood, such as attention and hyperactivity issues, as well as adverse behaviour
  • performing poorly at school.

(NICE, 2010; RCOG, 2015)

When a woman stops smoking during pregnancy, all the risks described above decrease (RCOG, 2015).

How to stop smoking when pregnant

Stopping smoking in pregnancy at any time has a positive impact on your baby’s life as well as your own. The sooner you stop, the more it benefits you and your baby (NHS, 2017).

Research shows that more women quit smoking when they’re pregnant than at other time in their lives. Up to 45% of women who smoked before they got pregnant suddenly stopped ahead of their first antenatal appointment (Coleman et al, 2015).

Pregnant women who smoke during pregnancy are referred to a specialist midwife or stop smoking adviser for support. This will happen even if they quit up to two weeks beforehand. Support usually takes the form of one-to-one appointments to help you deal with cravings for cigarettes and other withdrawal symptoms (RCOG, 2015).

If your partner or close family members also smoke, they can support you by joining you in giving up. This can really help boost your motivation to quit. Because it’s so important you both stop, they should be given support too (RCOG, 2015).

Your midwife and GP will be very supportive if you decide to stop smoking. There are several other sources from where you can get help and support, including:

  • calling the NHS Smoking Helpline on 0300 123 1044 or local helpline number if available
  • the NHS Smokefree website
  • the NHS website.

(RCOG 2015).

Passive smoking and pregnancy

Even if you don’t smoke, people smoking around you – secondhand smoke or passive smoking – can seriously affect you and your baby’s health. There are many risks to unborn babies exposed to passive smoking, some of which are:

  • stillbirth
  • preterm birth
  • poor health and growth of baby
  • low birth weight.

(RCOG, 2015; NHS, 2017).

To keep yourself and your baby safe, ask smokers to smoke outside the house or car and try to remain away from them while they are smoking (RCOG, 2015).

Use of stop smoking aids when you are pregnant

Some products can make it easier for you to quit. Nicotine replacement therapy (NRT) comes in several forms, including patches, chewing gum, lozenges or mouth spray. These deliver ‘clean’ nicotine and are considered safe. They can really help if you’re trying to give up.

Nicotine replacement therapy doesn’t contain any poisonous substances like carbon monoxide or tar, but provides some nicotine to help you cope with the withdrawal symptoms (RCOG, 2015). That means it’s better to use NRT to help you give up rather than smoke during pregnancy.

During NRT, the dose of nicotine is reduced slowly. When smokers are considered able to stop without suffering too much from withdrawal symptoms, the dose is stopped (Coleman et al, 2015).

The use of electronic cigarettes is also increasing as an alternative to tobacco smoking. Yet it’s not always clear what’s in them, and they might contain other damaging substances besides nictoine. So using electronic cigarettes is not advised during pregnancy as the long-term risk to your unborn baby is unknown (RCOG, 2015).

Last reviewed and updated in March 2018

Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

We also offer antenatal courses that are a great way to find out more about birth, labour and life with a new baby.

The NHS Smokefree helpline is open 9am-8pm Monday to Friday, and 11am-4pm at weekends. The helpline on 0300 123 1044 offers help, support and advice on how to stop smoking during pregnancy and can provide details of local support services. You can find more information on the effects of smoking and support on quitting to smoke on the NHS Smokefree pages. Smokefree also offers information specifically for dads.

QUIT is the UK charity that helps smokers to stop and young people to never start. Information on smoking in pregnancy is available as is information specifically for young smokers. 

Quitbecause offers information specifically for young smokers.

NHS Digital. (2017) Statistics on women’s smoking status at time of delivery, England – quarter 4, 2016-17. Available at: [Accessed 1st March 2018]

NHS. (2017) Stop smoking in pregnancy. Available at: [Accessed 1st March 2018]

RCOG. (2015) Smoking and pregnancy. Available at: [Accessed 1st March 2018]

NICE. (2010) Smoking: stopping in pregnancy and after childbirth. Available at: [Accessed 1st March 2018]

Coleman T, Chamberlain C, Davey M, Cooper SE, Leonardi-Bee J. (2015) Pharmacological inteventions for promoting smoking cessation during pregnancy. Cochrane Pregnancy and Childbirth Group. Available at: [Accessed 1st March 2018]

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