Mother’s Smoking Linked To Oral Birth Defect

A new study shows that pregnant women who smoke [smoking during preganancy] or regularly breathe second-hand smoke may be raising the odds that their baby will be born with a cleft lip.

Cleft lip and cleft palate are among the most common types of birth defect. They arise when the tissues that form the roof of the mouth and the upper lip do not fuse properly, sometime between the fifth and ninth week of pregnancy.

In the current study, Norwegian researchers found that women who smoked more than 10 cigarettes per day during their first trimester [first trimester pregnancy] were nearly twice as likely to have a baby with a cleft lip as nonsmokers were.

Similarly, nonsmoking women who were near a smoker for at least two hours each day had a 60 percent higher risk than women who were not exposed to passive smoking.

Past studies have linked mothers’ smoking to cleft lip and, less consistently, to cleft palate.

The new findings add that to that evidence, and also suggest that smoking affects the odds of cleft lip regardless of certain genes.

Lie’s team assessed 1,336 infants — 573 of whom had an oral cleft — for several variations in “detoxification” genes believed to help the body rid itself of tobacco smoke toxins. In most cases, their parents were assessed as well.

Read more information at Reuters