Pregnancy and smoking

Smoking while pregnant exposes you and your unborn child to an increased risk of serious health problems. Passive (second-hand) smoking can also affect you and your baby. Surveys show that a significant number of women still smoke during pregnancy.

If you smoke while pregnant, you are at increased risk of a wide range of problems, including miscarriage and premature labour. You are about twice as likely to give birth to a low birth weight baby compared with a mother who does not smoke. Low birth weight babies face a greater risk of death and are more vulnerable to infection, breathing difficulties and long-term health problems in adulthood.

The more cigarettes you smoke during pregnancy, the greater your risk of complications and of having a low birth weight baby. Cutting down the number of cigarettes does not reduce most of these risks. Stopping completely, as early in pregnancy as possible, best protects the health of you and your baby. Quitting at any time still helps reduce harm.

How smoking affects pregnancy#

Some of the pregnancy complications more commonly experienced by women who smoke include:

• ectopic pregnancy (a pregnancy that develops outside the uterus, usually in the fallopian tube)
• miscarriage (spontaneous abortion)
• stillbirth (death of the baby in the uterus)
• problems with the placenta, including early detachment from the uterine wall, or the placenta covering the cervical opening (placenta praevia)
• premature rupture of the membranes
• premature labour

Every time you smoke a cigarette while pregnant, it reduces the oxygen reaching your baby and exposes them to many toxic chemicals.

How smoking affects your unborn baby#

Some of the many damaging effects of cigarette smoke on your baby include:

• a reduced supply of oxygen and nutrients, because of the carbon monoxide and nicotine in tobacco smoke
• slower growth and development
• harm to the development of the baby’s brain and lungs
• an increased risk of birth defects such as cleft lip and cleft palate
• weaker movements in the womb for at least an hour after each cigarette
• impaired development and functioning of the placenta

Effects that can last into childhood#

Smoking during pregnancy can affect your child’s health for years to come. Possible effects include:

• low birth weight, which is linked to heart disease, type 2 diabetes and high blood pressure in adulthood
• up to three times the risk of sudden unexpected death in infancy (SUDI)
• an increased risk of attention deficit hyperactivity disorder (ADHD)
• weaker lungs and a higher risk of asthma
• an increased risk of being overweight or obese in childhood

Smoking and breastfeeding#

Stopping smoking while breastfeeding is very worthwhile. Some of the problems caused by smoking while breastfeeding include:

• Nicotine and other chemicals in cigarette smoke can pass to your baby through your breast milk.
• Smoking can reduce your milk supply and the quality of your breast milk.
• It increases your baby’s risk of health problems such as colic and disrupted sleep patterns.

Women who smoke are less likely to breastfeed and tend to wean their children earlier than mothers who do not smoke. Breastfeeding has many benefits, including helping to protect your child from chest and ear infections and illnesses of the gut.

If you are finding it hard to stop smoking:

• Try not to smoke before or during feeds.
• Breastfeed your baby first, then have your cigarette soon after, to give your body the longest time possible to clear nicotine from your breast milk. Do the same if you are using a nicotine lozenge, mouth spray, gum or inhalator.
• Do not smoke near your baby. Go outdoors to smoke.

Getting help to quit#

Talk to your doctor or maternity care team about how they can help you, and make a quitting plan together. Telephone and online quit-smoking counselling services can provide free support during your pregnancy and for some time afterwards to help you stay smoke-free.

If you are finding it tough to stop, do not despair. It is never too late to stop smoking. Stopping by about the fourth month of pregnancy can reduce some risks, such as low birth weight and premature birth, and stopping at any time allows oxygen to reach your baby more easily.

Nicotine replacement therapy#

It is recommended that you first try to stop smoking without medication. However, if you are unable to quit, you may use nicotine replacement therapy (gum, lozenges, mouth spray, an inhalator, or 16-hour patches) to help you. While using these products is considered safer than smoking, even this smaller amount of nicotine may not be entirely risk-free for your baby.

If you are pregnant, talk with your doctor before using nicotine replacement therapy so you can discuss the risks and benefits. A quit-smoking counselling service can also help you decide what support is best for you.

Key points#

• Smoking while pregnant exposes you and your unborn child to an increased risk of serious health problems.
• Cutting down the number of cigarettes does not reduce most of the risks to you and your baby; stopping completely is best.
• Smoking during pregnancy raises the risk of low birth weight, SUDI, ADHD and other long-term problems.
• It is never too late to quit, and your doctor, maternity team or a quit-smoking service can support you.

Where to get help#