A new study researching the effect of smoking on unborn babies has found risks even more widespread than those already known.
Researchers at the University College London looked at studies from the past 50 years examining how smoking affects pregnancy outcomes and found a strong link between smoking and cleft lip, cleft palate, congenital heart disease and other birth abnormalities, reported Time Magazine's Healthland writer Bonnie Rochman.
"The London study looked at nearly 174,000 cases of malformations, compared with close to 12 million control cases, to conclude that cigarette chemicals including nicotine, carbon monoxide and tar can lead to limb deformities, clubfoot and gastrointestinal and optical disorders, not to mention stillbirth — when a baby dies in utero more than halfway through the pregnancy — and premature birth," Rochman wrote.
Regardless of this study and other evidence that smoking during pregnancy causes significant birth defects, the Los Angeles Times reported a March of Dimes statistic that 20 percent of women still smoke while pregnant. The majority are pregnant teenagers, poorly educated women and economically disadvantaged women.
In the past, exact numbers for birth defects connected to smoking have been difficult to measure, but Allan Hackshaw of the University College London Cancer Institute, who led the study, pinned down some numbers from their data, the Times said.
Smoking while pregnant increases the risk of:
Skull defects by 33 percent
Clubfoot by 28 percent
Cleft lip or cleft palate by 28 percent
Gastrointestinal defects by 27 percent
Missing or deformed limbs by 26 percent
Heart defects by 10 percent
Gastroschisis (parts of the stomach or gut protrude through the skin of the abdomen) by 50 percent
Hackshaw and his colleagues also found that in addition to these risks, women who smoke have a higher chance of having a baby with two or more birth defects, CNN reported.
"(The) overwhelming trend is that (smoking) is harmful," Michael Katz, senior vice president for research and global programs of the March of Dimes, told CNN. "Any woman who is pregnant and smokes endangers not only herself, but her unborn child."
Time Magazine reported that statistics from the 14th World Conference on Tobacco or Health (Mumbai, 2009) show 250 million women worldwide use tobacco daily, but Katz hopes that this new research will motivate some to quit.
Although Hackshaw's study doesn't explain exactly how smoking creates these risks, the 4,000 different chemicals in cigarette smoke could be what interferes with fetal development, while the carbon monoxide in the smoke impairs blood circulation and limits the oxygen supply, according to the Los Angeles Times.
"Now that we have this evidence, advice should be more explicit about the kinds of serious defects…that babies of mothers who smoke during pregnancy can suffer from," Hackshaw told the LA Times. "The message from this research is that women should quit smoking before becoming pregnant, or very early on, to reduce the chance of having a baby with a serious and lifelong physical defect."
EMAIL: rcampbell@desnews.com