"Of all the harmful exposures in pregnancy, it is arguably smoking which causes the greatest harm. Not only does it cause impaired fetal growth, low birth weight and preterm birth, it is also associated with an increased risk of miscarriage, stillbirth, neonatal death and sudden infant death syndrome (SIDS).” Annual Report of the Chief Medical Officer 2012. Our Children Deserve Better: Prevention Pays.1
Smoking during pregnancy is harmful to both the mother and their unborn child. It is the main modifiable risk factor associated with a range of poor pregnancy outcomes.
Up to 2,200 premature births, 5,000 miscarriages and 300 perinatal deaths every year in the UK are caused by smoking, with further risk associated with exposure to secondhand smoke. It also increases the risk of developing a number of respiratory conditions; attention and hyperactivity difficulties; learning difficulties; problems of the ear, nose and throat; obesity; and diabetes 2,3,4.
Although rates are lower than in the past, around 11% of women in England are recorded as smoking at the time of delivery, which translates into more than 70,000 infants born to smoking mothers each year5.
There are still significant differences across regions and social groups – with the burden and harm hitting hardest in more deprived communities. For instance, pregnant mothers under the age of 20 are more than three times as likely to smoke as mothers aged 35 or over. Those in routine and manual occupations are more than four times as likely as those in managerial and professional occupations to smoke throughout pregnancy (29% and 7% respectively). Infants born to smokers are much more likely to become smokers themselves, which further perpetuates health inequalities.
It is important to identifying women who smoke as early in their pregnancy as possible and refer them for specialist stop smoking support. For some women it can be hard to admit they are still smoking and many will find it difficult to quit. The Smokefree and Start4Life websites provide useful information and resources for women and their families and the NCSCT has a written briefing for midwifery teams to help with raising and addressing this issue. A new on-line training module is also in development and will be available on the RCM iLearn platform soon.
There are also resources for both midwives and pregnant women to help explain the dangers associated with carbon monoxide (CO). CO is present in exhaust fumes, faulty gas appliances, coal/wood fires, oil burning appliances and cigarette smoke. It is especially dangerous during pregnancy because it deprives the baby of oxygen, slows its growth and development, and increases the risk of miscarriage, stillbirth and sudden infant death. This is why it is important to offer and encourage pregnant women to have a CO screening test, ideally at all antenatal appointments.
Being smokefree is the best thing a woman and her partner can do to protect their own health and the health of their baby, both during pregnancy and after. Stopping smoking early in pregnancy can almost entirely prevent damage to the baby. It is never too late to stop, but the earlier the better. Quitting and remaining smokefree can be difficult, and like many smokers expectant parents may need help, so we would encourage all health professionals to engage with women and their families on this issue, use the resources that are available to provide information and refer all smokers to their local stop smoking service for specialist support.
Jo Locker, Tobacco Control Manager, Public Health England
1 Annual Report of the Chief Medical Officer 2012. Our Children Deserve Better: Prevention Pays - https://www.gov.uk/government/publications/chief-medical-officers-annual-report-2012-our-children-deserve-better-prevention-pays
2 Royal College of Physicians (2010) Passive Smoking in Children - https://www.rcplondon.ac.uk/sites/default/files/documents/passive-smoking-and-children.pdf.
3 NICE Guidance PH26 (2010). Quitting Smoking in Pregnancy and Following Child Birth http://www.nice.org.uk/guidance/pH26
4 Challenge Group Report (2013). Smoking cessation in pregnancy: A call to action - http://ash.org.uk/files/documents/ASH_893.pdf
5 HSCIC (2015). Smoking at Time of Delivery (SATOD) - http://www.hscic.gov.uk/catalogue/PUB17668
6 HSCIC (2010). Infant Feeding Survey (IFS) - http://www.hscic.gov.uk/article/2021/Website-Search?productid=9569&q=Infant+Feeding+Survey+&sort=Relevance&size=10&page=1&area=both#top
7 Godfrey C. et al. (2010). Estimating the costs to the NHS of smoking in pregnancy for pregnant women and infants. York: Department of Health Sciences, The University of York.