If you smoke and you are pregnant or planning to become pregnant, you are strongly advised to stop smoking. This is to benefit your health and the health of your baby. Seek help from your pharmacist, practice nurse or GP if you find it difficult to stop smoking, or contact national stop smoking services.

Why is smoking harmful in pregnancy?

Tobacco smoke contains poisonous chemicals which pass into your bloodstream when you smoke, and then on into the growing baby's blood. Smoking when you are pregnant gives a higher risk of:

• Having a aborto espontáneo.

• Having a pregnancy which does not develop in the normal place (embarazo ectópico).

• Slow growth of the baby leading to a low birth weight.

• Parto prematuro.

• Bleeding towards the end of pregnancy, due to the placenta coming away from the wall of the womb (uterus) early. This is called placental abruption. The placenta is the tissue which supplies the nutrients the baby needs, so this may harm the baby.

• Mortinato.

• Your baby having abnormalities such as a cleft lip or palate.

Even after the birth, children of smoking parents have an increased risk of:

• Infecciones del pecho.

• Asma.

• Glue ear.

• Cot death (sudden infant death syndrome).

• Doing less well at school.

• Behavioural problems such as attention deficit hyperactivity disorder (ADHD).

Stopping smoking reduces all these risks. Of course, there are many other risks with smoking, such as the increased risk of developing chest and heart disorders. See the separate leaflet called Quit Smoking (Smoking Cessation) for more details.

You and your baby will get most benefit and the risks will be most reduced if you stop before you become pregnant. Planning to become pregnant is a good incentive to stop smoking for many women. It is also often a good time to persuade partners to give up too. However, your baby will still gain some benefit if you stop at any point during pregnancy.

For many people it is not easy to stop. Below are some tips which may help:

• Write a list of all the reasons why you want to stop, and keep it with you. Refer to the list when you are tempted to light up.

• Set a date for stopping and stop completely. Studies suggest that stopping completely is more effective than reducing gradually.

• Tell everyone. Friends and family often give support and may help you.

• Get rid of ashtrays, lighters and all cigarettes.

• Be prepared for some withdrawal symptoms. When you stop smoking, you are likely to get symptoms which may include feeling sick (nausea), headaches, anxiety, irritability, craving and just feeling awful. These symptoms are caused by the lack of nicotine that your body has been used to. They tend to peak after 12-24 hours and then gradually ease over 2-4 weeks.

• Be aware of situations in which you are most likely to want to smoke. (Remember, even though UK pubs have No Smoking policies, there may be outdoor smoking areas.) Try changing your routine for the first few weeks. If drinking tea and coffee are difficult times, try drinking mainly fruit juice and plenty of water.

• Take one day at a time. Mark off each successful day on a calendar. Look at it when you feel tempted to smoke, and tell yourself you don't want to start all over again.

• Be positive. You can tell people that you don't smoke. You will smell better. After a few weeks you should feel better, taste your food more and cough less. You will have more money.

• Alimentos. Some people worry about gaining weight when they give up smoking, as the appetite may improve. Anticipate an increase in appetite and try not to increase fatty or sugary foods as snacks. Try fruit and sugar-free gum instead.

• Don't despair if you fail and have a cigarette. You don't have to start smoking again. Pick yourself up and try again. Examine the reasons why you felt it was more difficult at that particular time. It will make you stronger next time.

• Get support. Specialist advisers from national stop smoking services can help with support, strategies and information. Contact details are available online.

Terapia de reemplazo de nicotina

If withdrawal symptoms are troublesome, nicotine replacement therapy (NRT) may help. Nicotine gum, sprays, patches, tablets, lozenges and inhalers are available to buy, and on prescription. Using one of these increases your chance of stopping smoking if you really want to stop. A pharmacist, GP or practice nurse can advise about NRT:

• If you are not yet pregnant but are planning a pregnancy, an option is to try a course of NRT before becoming pregnant.

• If you are pregnant, you can still consider using NRT. NRT is a medicine and may have effects on the baby. But, many people argue that NRT is safer than smoking as, unlike smoking, NRT just gives you nicotine. Smoking gives you nicotine plus a lot of toxic chemicals. So, if NRT does enable you to stop smoking, it may be worthwhile to take it even if you are pregnant.

See the separate leaflet called Nicotine Replacement Therapy (NRT) for more details.

Other medicines - can be used before you become pregnant

Medicines called bupropion (Zyban®) y varenicline (Champix®) can help. These are available on prescription. One of these may be useful antes you become pregnant. These medicines roughly double your chance of stopping smoking if you really want to stop. They help to reduce the symptoms of nicotine withdrawal. But note:

• You should not take these medicines when you are pregnant, as the risk to the unborn child is not known.

• If you take one of these medicines, the course should be completed before you become pregnant.

See the separate leaflets called Bupropión (Zyban®) y Varenicline (Champix®).

You will get different advice from different authorities on this one, so be prepared for confusion! Some authorities, such as the Royal College of Obstetricians and Gynaecologists (RCOG) in the UK, or the Centers for Disease Control and Prevention (CDC) in the USA, advise against the use of e-cigarettes in pregnancy. This is because there is not currently enough evidence to be sure they are safe when you are pregnant. Other authorities, however, such as the Smoking in Pregnancy Challenge Group, feel the risk of e-cigarettes is lower than the risk of continuing smoking.

This group advises that although nicotine replacement therapy (NRT) is the preferred method of quitting, if a medicinal product is needed, e-cigarettes are safer than continuing to smoke. It is likely that more information will become available in the next few years about safety in pregnancy. Meanwhile the safest approach is probably to see it as a last resort if you are unable to stop smoking any other way in pregnancy.