Children More Likely to Smoke if Mom Smoked During Pregnancy

< May. 20, 2009 > -- According to researchers from the University of Arizona, smoking during pregnancy "biologically primes" a fetus to become a regular smoker as a teen and young adult.

"Somehow smoke is changing the brain chemistry," says the lead researcher, Dr. Roni Grad, an associate professor of clinical pediatrics at the University of Arizona.

"If you are exposed to smoking prenatally or in the early years of life, you are much more likely to be a chronic smoker at the age of 22," Dr. Grad says.

On Tuesday, at the American Thoracic Society's 105 International Conference in San Diego, study results were presented indicating that children of mothers who smoked during pregnancy are four times more likely to become regular smokers.

Research Study and Results

Data from the Tucson Children's Respiratory Study was used to determine if mothers who smoked during pregnancy and during their child's early years affected smoking behavior in these children later in life.

In this study, smoke exposure during pregnancy and the early years of life of their offsprings was assessed during pregnancy, at nine days, when their infants were 1.5 months and 1.5 years old, and when the children were six, nine, and 11 years of age. At 16 and 22 years of age, smoking behavior of these children was assessed again by researchers.

Based on study findings, maternal smoking and smoking during their children's early years were factors that may have caused their offsprings to smoke at the age of 22. This theory was validated whether the mother smoked or did not smoke during their offspring's school years.

In addition, an offspring of a mother who never smoked or who started smoking when their child was school-age was more likely to quit smoking than a child of a mother who smoked during pregnancy and the child's early years of life.

Study findings indicated that smoking histories of fathers or peer pressure during adolescence did not have an impact on a child's smoking behavior.

Smoking During Pregnancy

"Nobody should smoke," Dr. Grad says. "I would definitely discourage any mother from smoking around her child. If children have been exposed in early life to smoke, I would really go the extra mile to try to keep them from experimenting, because they may be at higher risk of becoming nicotine dependent very quickly."

Dr. Norman H. Edelman, a scientific consultant to the American Lung Association (ALA), says these research findings support reasons why women should not smoke before becoming pregnant.

"We know that smoking during pregnancy confers many health risks upon the fetus, including premature birth and increased risk for asthma," Dr. Edelman says. "Now we see a new risk - increased rates of smoking during subsequent early adulthood."

According to Dr. Edelman, the study seems to favor a biologic explanation - brain neurochemistry is affected during pregnancy. "However, the study does not include enough information to rule out social factors, such as increased smoking of others in the household even though the mother stops after childbirth."

"When you decide to become pregnant, there are certain steps to take to optimize the health of the hoped-for child, such as taking folic acid and weight reduction for the very overweight," Dr. Edelman adds. "Now, even more forcefully, we add stop smoking - and get others in the household to do so as well."

Danny McGoldrick, vice president for research at the Campaign for Tobacco-Free Kids, agreed that the study emphasizes the importance of not smoking during pregnancy.

"We already know how bad smoking during pregnancy is for the fetus and the health of the child," McGoldrick says. "This new research shows that smoking during pregnancy also makes the child more likely to become a smoker as an adult - even if the mother quits smoking when the child is young."

"Aside from protecting their own health, this is one more reason that female smokers who are pregnant or considering becoming pregnant should try to quit," McGoldrick adds.

Always consult your physician for more information.

Smoking and Pregnancy

Although fewer women are smoking during their pregnancy now than ever before, the habit still persists among many women. In addition, even if a pregnant woman does not smoke, she may be exposed to secondhand smoke in the household, workplace, or in social settings.

Smoke can be damaging to a fetus in several ways, and may cause low birth weight, preterm birth, stillbirths, and increased risk of birth defects.

Subsequently, babies born to smokers may also have poor lung development, asthma, and respiratory infections. An increase in sudden infant death syndrome (SIDS), physical growth deficiency, intellectual development deficiency, and behavioral problems have also been reported.

The mother, too, may experience problems during her pregnancy as a result of smoking, including, but not limited to, the following:

• placental complications

• preterm labor

• infections in the uterus

Researchers believe the effects of carbon monoxide (which reduces oxygen in the blood) and nicotine (which stimulates certain hormones) cause many of these adverse effects.

Babies of mothers who are regularly exposed to secondhand smoke during pregnancy are more likely to have reduced fetal growth and low birth weight.

However, according to the US Food and Drug Administration (FDA), if a woman quits smoking early in her pregnancy, she increases her chance of delivering a healthy baby.

Always consult your physician for more information.