Effects of smoking during pregnancy

The comprehensive list on this page shows all the known effects of
smoking during pregnancy



  • One of the most serious risks of the effects of smoking during pregnancy is the significantly higher chance of having a miscarriage or ectopic pregnancy.
  • Another complication of smoking's effects when pregnant is placenta previa, a condition where the placenta (the organ that nourishes the baby) grows too close to the opening of the womb, and usually requires a caesarean delivery.
  • Compared with non-smokers, pregnant smokers are up to two times more likely to deliver premature babies — the leading cause of stillbirth and death in the first month of life. Called placental abruption, the placenta separates from the wall of the womb earlier than it should.
  • Babies of smokers have less muscle mass and more fat than babies of nonsmokers. Nicotine causes the blood vessels to constrict in the umbilical cord and womb. This decreases the amount of oxygen to the unborn baby and reduces the amount of blood in the baby's system.

    Pregnant smokers actually eat more than pregnant nonsmokers, yet their babies get less sustenance and weigh less.

  • The above effects of smoking during pregnancy means a 10 fold increase in the likelihood of carrying smaller babies (called intrauterine growth retardation) and for mothers who continue smoking while pregnant, they risk delivering low-birth-weight babies 3.5 more times than non-smoking mothers — with all the attendant health risks.
    (When mothers quit smoking during the first 3 months, their babies have weight and body measurements similar to babies of nonsmokers; and quitting before the last 3 months still makes it more likely their babies will be close to normal weight.)
    (See BMJ)

    • Testing done throughout life, shows that at the top end of a normal birthweight range, general brightness was higher and children and adults performed better in thinking and memory tests, than those born lighter.
    • Mothers who smoke while pregnant are 50 percent more likely than nonsmoking mothers to have a child with mental retardation (IQ of 70 or less) of an unknown cause. (See MR)
    • Testing at age 7 years shows that for a 2.2lb increase in birth weight there is a 4.6 point gain in IQ for boys and a 2.8 point IQ gain in girls.
    • Especially in baby boys, there is less chance of respiratory distress and complications with a normal weight than with a low birth weight baby.

  • One of the biggest risks from the effects of smoking during pregnancy comes from the combined effect of two previously mentioned symptoms... low birth weight and premature delivery. 10% of these babies have Infant Respiratory Distress Syndrome, whereby the immature lungs have not developed normal surfactant coating and the air sacs collapse.

    Modern treatment has helped lower the death rate and prognosis for this dangerous and heart-wrenching condition.
    (American president, John F Kennedy and Jackie Kennedy (smokers) in August 1963 lost a 2 day-old son to this condition. He was buried next to his previously stillborn sister).

  • Mothers who smoke during and after pregnancy have nearly 4 times the risk of losing their babies to Sudden Infant Death Syndrome (SIDS).

    If they take up smoking after giving birth, there is less risk but it's still double due to exposure to smoke. This is often caused not only by the toxins in tobacco, but by nicotine itself, which is a potential foetal teratogen. Nicotine replacement therapy during pregnancy is also hazardous for this reason.



Effects of smoking during pregnancy - claim your birthright to a happy, healthy family



Chilling Long term effects of smoking during pregnancy

  • Babies who survive having to receive oxygen at birth, particularly those who need large amounts because of severe respiratory distress syndrome, can develop long-term complications as a result of:

    - oxygen toxicity,
    - high pressures delivered to the lungs,
    - the severity of the condition itself,
    - or periods when the brain or other organs did not receive enough oxygen.

    Most of these complications are life-threatening or the baby is scarred for life and may need surgery, often more than once. They include:

    • Pneumothorax: Air caught in or around the lungs, resulting in sharp chest pains or tightness, coughing, rapid heart rate, lack of oxygen causing fatigue and bluish skin color. Similar conditions, but with air trapped in different places are Pneumonediastinum and Pneumopericardium
    • Bronchopulmonary dysplasia: A chronic lung condition requiring ventilator support of oxygen often for many months and lifetime management, and often developing recurrent respiratory infections. Babies have to be fed by a tube into the stomach, with high doses of corticosteroids, surfactants and bronchodilators.
    • Brain Hemorrhage: (intraventricular bleed)
    • Hemorrhage into the lung: (sometimes associated with surfactant use)
    • Thrombotic events: Blood clots, stroke, high blood pressure, and cardiovascular disease, associated with an umbilical arterial catheter
    • Retrolental fibroplasia: Causes eye problems such as scarring, detachment of the retina and blindness
    • Cerebral palsy, delayed mental development and mental retardation: Associated with anoxic brain damage (lack of oxygen to the brain) or hemorrhage (burst blood vessels).
  • Recent studies now link smoking by the mother directly with up to 4 times more risk for development of diabetes in the baby, and obesity and diabetes later in the child or adult. The assumption is that changes in the fetus' metabolism caused by smoking are responsible. Because the effects of smoking during pregnancy can cause a type of fetal malnutrition, this may lead to the baby's body assuming that it will be born into an environment where food will be scarce and lead to lifelong insulin resistance and a tendency to conserve fat. (See D)
  • Once a baby is born with damage caused by the effects of smoking during pregnancy, it's too late — there is a lifetime of regret for the parents. The suffering of their child can be enormous, sometimes for their entire lives, and most parents need emotional support.
  • Because hospitalization may be prolonged due to the very slow resolution of a disease, the costs on the parents can be overwhelming, and there is also the cost to society for support services, increased medical insurance costs and lost opportunities.
  • Finally, if a mother smokes during pregnancy and continues on smoking, she runs the risk of not only serious health problems, but also shortening both her life and her child's life. (Fact: 50% of all smokers die early of a smoking related disease.) That child will sadly be deprived of its mother earlier than he or she should.
  • In a nutshell — Want a healthy baby? Don't smoke.

    Good prenatal health and care, results in larger, healthier babies and fewer premature births...

    ...outstandingly brilliant reasons to quit smoking before or during pregnancy.


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