Smoking during pregnancy linked to cleft lip
NEW YORK, Apr 04 (Reuters Health) -- Smoking during pregnancy increases the risk of having a baby with cleft lip or palate, report US researchers.
These are two of the most common birth defects, affecting about 1 in 1,000 newborns. A new study shows that women who smoke during pregnancy are up to 70% more likely to have a baby with a cleft lip or palate than nonsmoking women.
``The most important point about this study is that women who smoke during pregnancy will have a higher risk for having a newborn with cleft lip or palate,'' lead author Dr. Kevin C. Chung told Reuters Health.
``Cleft lip and palate is a devastating disease in a child because of facial deformity and speech impairment,'' said Chung, an assistant professor of surgery at the University of Michigan Medical Center in Ann Arbor.
Although the cause of both cleft lip and cleft palate is unknown, there has been speculation that smoking during pregnancy may increase the risk. To confirm this theory, Chung and his colleagues analyzed national data of live births recorded in 1996. They identified over 2,200 cases of cleft lip or palate in babies born to women who smoked.
``In about 4 million births in the US in 1996, 13% of mothers reported to have smoked during pregnancy,'' Chung stated. ``This translates to a huge public health issue,'' he added. Other study findings, published in the journal Plastic and Reconstructive Surgery, show that the risk of cleft lip or palate increased with the number of cigarettes smoked -- ``up to 70% increased risk if they smoke greater than 21 cigarettes per day,'' said Chung.
In addition, mothers of newborns with cleft lip or cleft palate were more likely than nonsmoking women to have had pregnancy-related hypertension and to be diabetic, the authors note. These mothers also ``have a higher percentage of being non-black and a higher percentage of having less than a high school education,'' they write.
However, even after the data was adjusted for these factors, the investigators still found that mothers who smoked 1 to 10 cigarettes per day were 30% more likely to have children with cleft lip or cleft palate.
``Any amount of smoking during pregnancy is detrimental to the newborn,'' Chung stated. Furthermore, ``by not (smoking), the incidence of cleft lip and palate may decrease in this country,'' he added.
The researchers call for education campaigns to inform women about the risks of smoking during pregnancy. In addition to cleft lip and palate, these risks include prematurity and low birth weight.
``Increased public awareness has led women to generally avoid alcohol during pregnancy because of the risk of fetal alcohol syndrome,'' the team notes. ``Similarly, we strongly believe that educational initiatives must also be directed at expectant mothers to emphasize the deleterious effect of smoking in increasing the risk of having a child with cleft lip/palate.''