Smoking During Pregnancy – FAQ’s on Smoking During Pregnancy



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Smoking During Pregnancy – FAQ’s on Smoking During Pregnancy

When you smoke, poisons from tobacco smoke pass through your lungs and into your blood stream. They are carried around your body and interfere with the way it works. Every puff you take on a cigarette increases the carbon monoxide in your bloodstream which takes the place of oxygen in your blood. The nicotine in the smoke immediately increases your heart rate and blood pressure. It causes your blood vessels to narrow, reducing blood flow. The combination of these causes great stress to your body, especially your heart.


Over time, smoking starts to take its toll on your body. It depresses your immune system, interferes with your lungs clearing system, reduces blood flow to your hands and feet and hardens your arteries.

What Diseases Can Smoking Cause?

Smoking causes lung cancer, heart disease, stroke, emphysema and chronic bronchitis. Smoking also causes cancer of the throat, mouth, lip, tongue, nose, nasal sinus, voice box, oesophagus, pancreas, stomach, kidney, bladder, ureter, cervix, and bone marrow (myeloid leukemia).

Smoking causes blindness, loss of bone density, hip fractures, gum disease, peptic ulcers, and vein disease in your legs. Problems caused by smoking can be painful, crippling and long lasting. The earlier you quit, the more you reduce your risk of serious illness and early death.

What About Weight Gain?

Most people do gain some weight when they quit smoking. But research shows that in the long term, the average weight of ex-smokers is similar to women who have never smoked.

On average, smokers weigh slightly less than people who don’t smoke. This is thought to be due to the effects of nicotine, which suppresses hunger and speeds up the way the body processes food.

Weight changes also depend on things such as exercise and eating habits. Plan a range of healthy snacks. But be realistic, allow yourself some treats. Also, think about doing some exercise. For example, walk up stairs rather than take the lift, walk to the shops or around the block for exercise. This may even help you quit.

If worrying about putting on weight is stopping you from quitting smoking, act on your concerns. Talk to your doctor or dietician, and make a sensible eating plan. A lot of women who are concerned about putting on weight before they quit actually find that it isn’t the problem they thought it would be.

Smoking While Pregnant

If you smoke when you are pregnant the combination of carbon monoxide and nicotine in cigarettes makes it harder for your baby to get the oxygen and nourishment it needs. Smoking places stress on the baby’s heart and affects the development of its lungs.

Pregnant smokers have a greater risk of miscarriage, may have a difficult birth and risk having a low weight baby, which will be more vulnerable to infection and other health problems. The baby of a smoker is more likely to die at or shortly after birth.

If you quit before becoming pregnant or in the first few months, your baby’s birthweight will be the same as if you had been a non-smoker. Also, you reduce the risk of premature birth and other pregnancy complications.

What Happens To My Baby When I Smoke?

The umbilical cord is your baby’s lifeline. Blood flow through this cord provides your baby with oxygen and the food it needs to grow. Every puff you take on a cigarette has an immediate effect on your baby. Carbon monoxide replaces some of the oxygen in your blood, reducing the amount of oxygen received by your baby through the umbilical cord.

The nicotine in cigarettes increases your heart rate and your baby’s heart rate. It also causes your blood vessels to narrow, reducing the flow of blood through the umbilical cord. This makes it harder for your baby to get the oxygen and nourishment it needs.

To prepare for breathing after birth, your unborn baby will be practising by exercising some of its chest muscles. Nicotine reduces these breathing movements.

Cigarette smoke also contains many other harmful poisons, which pass through your lungs and into your bloodstream, which your baby shares.

Smoking during pregnancy by a mother is a major cause of sudden infant death syndrome (SIDS or ‘cot death’). It also has the following effects:

  • Increases the risk of miscarriage
  • Increases the risk of complications during the birth
  • Increases the likelihood of having a low-weight baby who is more vulnerable to infection and other health problems
  • Increases the chances of the baby dying at or shortly after birth.

Can Quitting Cold Turkey Harm My Baby?

There is no evidence to support the claim that quitting cold turkey could harm the foetus. On the contrary, every cigarette delivers many chemical agents that put the baby under stress. In particular, carbon monoxide displaces oxygen from red blood cells and makes it harder for the blood cells to release oxygen. This badly affects the transfer of oxygen from the mother’s blood to the baby’s blood across the placenta.

Tobacco smoke has very high levels of oxidising chemicals which upset important processes in the umbilical cord, constricting it. Their actions also impair the production of the membrane around the baby.

Smokers have more viscous (thicker and stickier) blood than non-smokers, which is a risk factor for stroke in the newborn as well as for blood clots (thrombosis) in the placenta. When the mother quits smoking, the level of carbon monoxide drops quickly and is much lower after only a day, and her blood improves over the next several weeks.


Smoking results in retarded growth of the foetus and subsequently low birth weight. Low birth weight may have a lasting effect of the growth and development of the child. It is associated with an increased risk for early puberty, and in adulthood an increased risk for heart disease, stroke, high blood pressure, and diabetes. Women who quit early in their pregnancy have babies with birth weights similar to non-smokers.

Women who quit smoking during pregnancy reduce the risk reduce the risk of preterm membrane rupture, preterm delivery and low birth weight.

In general, quitting without using quitting aids (nicotine replacement therapy or bupropion (Zyban) is preferred. This means first options are quitting suddenly or cutting down over one to two weeks and then quitting.

At the moment, there is nothing to recommend one method over the other, although quitting suddenly is more popular. Withdrawal symptoms might cause some emotional stress to the mother, which for most people is worse in the first week, but they decrease over time and usually do not last more than a few weeks. However, continued smoking puts the bodies of both mother and child under physical stress. All the evidence points to quitting smoking being one of the most important ways to improve pregnancy outcomes.

This is general information only and doesn’t take into account any individual medical history. If the mother has particular problems with withdrawal, for example taking other medication or depression, then she will need to seek appropriate medical advice and help.

Smoking and Breastfeeding

If you breastfeed you are giving your baby a good start in life. Breast milk provides all the nutrition your baby needs for the first six months of life, and the major part of nutritional requirements for the first year. It also helps protect your baby against infection.

As a breastfeeding mother, you have some control over your own and your baby’s environment – by not smoking and limiting your alcohol intake.

If you breastfeed and smoke it’s not ideal, but it is better than not breastfeeding. Women who smoke tend to produce less milk. Babies of smokers are more prone to chest illnesses, but breast feeding helps prevent these infections.

If you quit smoking, you will no longer be passing on nicotine and other poisons from cigarette smoke to your baby through your breast milk. You will also cut down your baby’s exposure to tobacco smoke, which will help protect your child’s health.

If you are having difficulty quitting, you can still help to reduce harm to your baby. Consider every cigarette and decide whether it’s worth it to you. Try not to smoke before or during feeds. Also try not to smoke near your baby – if you can, go outdoors to smoke. If you can’t give it up altogether, accept that for now, but keep working on it.

After the birth of your baby, smoking by either parent increases the risk of sudden infant death syndrome.

Common Smoking Fears and Myths

  • “There’s nothing wrong with having a low-weight baby – it just means a quicker and easier birth.”

Having a low-weight baby does not make things easier for you or your baby at birth. A smaller baby is more likely to become stressed during birth, leading to a more complicated delivery. Labour with a small under-weight baby is no easier or shorter than labour with an average baby.

  • “If I stop smoking I’ll put on too much weight.”

Some women find that smoking reduces appetite, but at what cost? You will need more calories during pregnancy to cope with the increased needs of your growing baby and to maintain your own health. A weight gain of 10 to 13 kilograms is considered desirable for the development of a healthy baby. A balanced, healthy diet consists of eating moderately from a wide variety of foods. It is the quality of your diet that is important, not the quantity of food eaten.

  • “Smoking relaxes me, and being relaxed is better for my baby.”

Smoking may calm you down, but it does speed up your heart rate, increases your blood pressure and depresses your nervous system. It cuts down the amount of oxygen and food reaching your baby. This is not better for your baby.

  • “Cutting down during pregnancy is good enough.”

Every bit helps, but even a few cigarettes a day means many poisons will be in your growing baby's food supply, and damaging your own health at a vital time. There is no safe level of smoking. Smoking lower tar/nicotine cigarettes is not likely to reduce the amount of poisons you inhale, as smokers tend to inhale more deeply and more often to get the amount of nicotine that they are used to.

  • “I’m already three months pregnant. What’s the point of stopping now? The damage is done.”

It is never too late to quit because most of the baby’s growth happens later in pregnancy. For example, if you quit now, your risk of having a low-weight baby will be similar to that of a non-smoker. Quitting at any time during pregnancy reduces the risk of harm to your baby. However, planning to quit as early as you can means a better start to life for your baby.

Quit Tips

Once you’ve decided you want to quit, make sure you’re successful by planning before you stop:

  • Throw away all cigarettes, lighters and ashtrays in your home and car. If your partner smokes, suggest that he stops too, or only smokes outside the house. Your children suffer if anyone smokes in your home.
  • Plan how to handle the places and events that you know make you want to smoke.
  • Talk to your family and friends about how they can help and encourage you to quit.
  • Treat yourself with the money you have saved. Your efforts deserve to be rewarded!
  • Remember each craving only lasts a few minutes. Use the 4Ds - delay smoking, deep breathe, drink water, do something else.
  • If you have a cigarette it’s not the end of your quit attempt. A slip-up is a setback, not a defeat.

If you are finding it difficult: Call the Quitline on 131 848 for a free Quit Pack and for information and support to help you quit smoking. Or visit Quit’s website http://www.quit.org.au

BellyBelly Recommends….

Allen Carr’s Easy Way To Stop Smoking – I have seen people literally put down this book and not pick up a cigarette ever again.

Reproduced with permission by
Quit Victoria
PO Box 888 Carlton Victoria 3053
Telephone (03) 9663 7777
© 2005

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