Pregnant Women Often Stamp Out Claims They Smoke

How do we say "she doth protest too loudly?" Next time you see a pregnant women dousing herself in perfume, stomping her feet and insisting that she does not smoke, even though she reeks of cigarette butts, trust your gut: She's lying.

One in four moms-to-be who smoke while they are pregnant, deny it, according to a study published in Reuters Health. This has significant implications, because smoking by moms-to-be is one of the most common preventable causes of illness and death among infants, says Patricia Dietz, a researcher for the division of reproductive health at the Centers for Disease Control and Prevention to Reuters.

Smoking for two? Credit: Getty Images

Though the numbers are most likely even larger especially for younger women in their 20s (some are better than others at being sneaky,) researchers studied pregnant and non-pregnant smokers aged 20 to 44 to see who would and wouldn't fess up on a health questionnaire, Reuters reports.

They zeroed in on the deception by taking blood samples from the women to measure levels of cotinine -- a byproduct of nicotine that serves as a marker of exposure to tobacco smoke, according to Reuters. Their analysis included 994 pregnant women and 3,203 non-pregnant women.

Overall, 13 percent of pregnant women and 30 percent of non-pregnant women were active cigarette smokers. The pregnant smokers smoked an average of 11 cigarettes a day, while the non-pregnant smokers averaged close to 14 cigarettes a day, Reuters reports.

But, more pregnant than non-pregnant women smokers failed to disclose their habit -- 23 percent versus nine percent -- and were identified by their cotinine concentrations, the report states.