Cells taken from the fetuses of women who had smoked at least 10 cigarettes per day for at least 10 years were more than three times as likely as cells taken from the fetuses of nonsmokers to have structural chromosomal abnormalities, according to a study published in the March 9 issue of the Journal of the American Medical Association, the Washington Times reports (Howard Price, Washington Times, 3/10). Although numerous studies have shown that cigarette smoking during pregnancy causes various adverse effects for developing fetuses, previously, only indirect data have suggested that exposure to cigarette smoking can cause genetic mutations in fetuses. To determine if there is a connection between maternal smoking and damage to fetal chromosomes, Rosa Ana de la Chica and colleagues from Universitat Autonoma de Barcelona in Spain analyzed fetal cells obtained during routine amniocentesis on 50 pregnant women. Half of the women reported smoking at least 10 cigarettes per day for at least 10 years, and the other half were nonsmokers (Reuters Health, 3/8). All of the women reported abstaining from alcohol, coffee and caffeinated tea during pregnancy (Washington Times, 3/10). The researchers found that the rate of the structural chromosomal abnormalities was 12.1% among the fetal cells collected from smokers, compared with 3.5% among cells collected from nonsmokers. The most common chromosomal mutation detected in the cells of smoke-exposed fetuses was in chromosome 11, where mutations have been linked to cancers of the blood, such as leukemia (Reuters Health, 3/8). The researchers said the study raises the possibility that smoking during pregnancy might put infants at risk of developing cancer later in life, BBC News reports.

Accompanying Editorial
In an accompanying JAMA editorial, Drs. David DeMarini and Julian Preston of the Environmental Protection Agency write that while the study has flaws, including no scientific measure of the level of fetal tobacco exposure and self-reported information about smoking and other habits, some previous research has indicated that tobacco smoke can lead to mutations in a developing fetus's genetic material. Despite the need for additional research, DeMarini and Preston say that the message should remain "clear" that "smoking during pregnancy can be hazardous for both the fetus and the mother," according to BBC News (BBC News, 3/9).