FRIDAY, March 28 (HealthDay News) -- Men typically continue to smoke and drink while their female partner is pregnant and after she's given birth, which can make it difficult for women to stop smoking and drinking during pregnancy and more likely to resume such habits after their child is born, a University of Washington study says.

"The months after childbirth are critical for intervening with mothers," study co-author Jennifer Bailey, a research scientist affiliated with the Social Development Research Group in the UW's School of Social Work, said in a prepared statement.

"For example, many already have done the hard work of quitting smoking and haven't smoked a cigarette in six months or more. We should support that effort so that they can continue as nonsmokers. However, we know if dad is smoking or drinking, it is more likely that mom will resume smoking or drinking," Bailey said.

She and her colleague Karl Hill, a research associate professor of social work, studied hundreds of Seattle mothers' and fathers' month-by-month substance use over a three-year period that included pregnancy. They found that:

• 77 percent of female cigarette smokers and 50 percent of female marijuana smokers used those substances at some time during pregnancy.
• 38 percent of female cigarette smokers and 24 percent of marijuana users said they used these substances throughout their pregnancies.
• Overall rates of women's use of cigarettes, marijuana and alcohol declined during pregnancy, but the rates of use started to increase during the first six months after giving birth.
• Month by month during pregnancy, rates of smoking among women varied between 7 percent and 21 percent, rates of binge drinking varied between 2 percent and 3 percent, and rates of marijuana use varied between 8 percent and 9 percent.

The researchers said their findings highlight the need for more public health education and intervention.

"Women who are pregnant want the best for their baby and typically reduce their drinking and smoking. But after birth, part of their motivation to limit alcohol use and quit using cigarettes and marijuana is taken away. If their partner is still smoking, for example, they might think, 'Boy, that cigarette smells good,'" Bailey said.

"There are two ways we need to reach parents," Hill said in a prepared statement. "Pregnancy health-care providers need to talk to both fathers and mothers about their smoking, drinking and marijuana use. Pregnancy seems like such a great public health opportunity to reach parents, but no one is talking to dads, and this study shows that they are not changing their substance use behavior. What dads do matters, and we want them to reduce their substance use."

More information

The American Lung Association has more about smoking during pregnancy.

SOURCE: University of Washington, news release, March 2008