"Smoking by Pregnant Women May Result in Fetal Injury, Premature Birth, and Low Birth Weight," the Surgeon General has long warned.
But while fewer pregnant women smoke now than a decade ago, a recent CDC report shows that 1 in 10 women still smoke while pregnant.
The prevalence of this public health hazard varies widely across the country, from 2.3 percent of pregnant women in New York City to 30.5 percent in West Virginia.
These numbers are not just women who smoked a little before they realized they were pregnant — these are women who reported smoking during the last three months of their pregnancies.
Here's a map that shows which states are the worst offenders:
Prevalence of smoking during pregnancy, 2010
Part of that variation comes not only from how many women smoke in each state before pregnancy, but how many women decide that getting pregnant is a good reason to quit. Seventy-five percent of New York City women quit during pregnancy; only about a third of West Virginia women do the same. (Throughout the country, an average of 54.3 percent of women quit by their last trimester.) The CDC also warns that since the numbers are self-reported, pregnant women who feel guilty might under-report smoking and over-report quitting.
It's not all bad news: The percentage of smokers in the U.S. is declining, and pregnant women are less likely to smoke than men and women in general.
Here's a chart that shows how many pregnant women smoke compared to other groups:
Cigarette smoking among men, women, high school students, and mothers during pregnancy: United States
For the full state-by-state breakdown of pregnant smokers, check out the CDC report: Trends in Smoking Before, During, and After Pregnancy.
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