Helping expectant moms stop smoking

Having given birth to four premature babies, Evelyn Rivera has experienced the problems that smoking during pregnancy can cause.

Now pregnant with her fifth child, Rivera has finally quit.

She credits a regimen of counseling and nicotine gum offered as part of a national study aimed at making it easier for pregnant women to quit, or at least reduce the number of cigarettes they smoke.

“Smoking is one of the most modifiable causes of poor pregnancy outcomes in the United States,” said Dr. Cheryl Oncken, an internist and associate professor of medicine and obstetrics and gynecology at the University of Connecticut Health Center.

Oncken has been awarded a $1.6-million research grant from the National Institutes of Health to study whether nicotine gum can help pregnant smokers quit and, if they cannot, whether the gum can contribute to healthier births by helping expectant mothers to smoke less.

Studies have found that smoking is responsible for 10% of infant deaths, that it doubles the risk of low birth weight and that it increases the risk of miscarriage by 30% to 50%.

Despite the risks, national statistics suggest that about 20% of pregnant women smoke, and the rate of those who quit during pregnancy is minuscule.

Oncken said she decided to try adding nicotine gum to conventional smoking-cessation counseling to see if it might help.

The U.S. Public Health Service has issued guidelines for quitting that call for a combination of counseling, social support and drugs such as nicotine-replacement products.

Tobacco-dependence researchers have found that the drug-and-counseling combo is more effective than either approach alone.

But so far, pregnant women have been asked to go cold turkey because of concerns that nicotine-replacement products, such as gum or a patch, might be harmful to the fetus.

Oncken said she understands that concern but noted that tobacco smoke contains 4,000 chemicals, including 69 cancer-causing agents. Also, the smoke in the lungs can reduce the oxygen supply to a growing fetus.

She said researchers in Denmark who studied 250 pregnant smokers found that the group using a nicotine patch had significantly bigger babies than those without it, although the rate of quitting was not much higher in the nicotine patch group.

Oncken said she hopes her study will find that nicotine gum helps women quit smoking, but she also plans to measure birth weight to learn whether smoking less during pregnancy can have some benefit.

“Quitting early is best,” Oncken said. “But even women who quit later have beneficial effects because of the exponential growth later in pregnancy.”