Pregnant women who smoke may put their kids at risk for severe asthma

One of the first questions a mom-to-be is asked by her doctor is "Do you smoke?"  And while pregnant woman don't smoke in nearly the numbers they did decades ago, some still do.   Almost 14% of American women smoke while pregnant, according to the Centers for Disease Control, causing all kinds of problems  including low birth weight, premature birth and SIDS.  Now add something else to the list: asthma.

An intriguing new study suggests African-American and Latino children with asthma whose moms smoke while pregnant are more likely to have severe asthma as teens, even if their moms stop smoking after they are born.

Researchers at the University of California San Francisco looked at about 2,500 Latino and African-American children with asthma. After controlling for things like poverty and childhood exposure to tobacco smoke, they found children of women who smoked while pregnant were 50% more likely to have asthma that was harder to control when compared to children with asthma whose mothers didn't smoke during pregnancy.  "Kids who are 17 years old still show the effects of something they were exposed to during the first nine months of their life," says researcher Dr. Sam Oh, of the University of California San Francisco Center for Tobacco Research and Education.  The study didn't look at Caucasian children.

Close to 19% of African American, 6% of Puerto Rican and just less than 4% of pregnant Mexican women smoke, according to the CDC.

"Something is happening during pregnancy that has an effect we believe leads to genetic imprinting," says Oh.  In other words, if mom smokes, her child's DNA changes.  He adds more research needs to be done in light of the high prevalency of asthma among minorities.

The study is published in the Journal of Allergy and Clinical Immunology .