Feb. 28 (UPI) -- One in 14 women who gave birth in the United States in 2016 said they smoked while they were pregnant, according to data released Wednesday by the Centers for Disease Control and Prevention.
The CDC gathered the information from its National Vital Statistics System, which is based on information from all birth certificates in the United States. Women self-reported whether they smoked.
They smoked even though maternal tobacco use during pregnancy has been linked to low birthweight, preterm birth and various birth defects, according to the CDC.
Smoking rates varied by states and a number of demographic breakdowns.
"Any amount of smoking during pregnancy is too much," Patrick Drake, senior author of the report and a demographer at the CDC's National Center for Health Statistics, told CNN.
The 7.2 percentage of women who smoked is lower than it was in 2011, when about 10 percent of women in the United States reported smoking during their last three months of pregnancy. And among the women who smoked, 55 percent quit while they were pregnant, according to data from the CDC's Pregnancy Risk Assessment and Monitoring System.
The smoking rate was highest in West Virginia at 25.1 percent, followed by Kentucky at 18.4 percent, Montana at 16.5 percent and Missouri at 15.3 percent.
It was the lowest in California at 1.6 percent, followed by Utah at 3.0 percent, Texas at 3.3 percent, Hawaii at 3.6 percent and New Jersey at 3.9. The District of Columbia's percentage was 2.6 percent.
Among age groups, the smoking rate was 10.7 percent among women 20 to 24, followed by women 15 to 19 at 8.5 percent and 25 to 29 at 8.2 percent.
Smoking was highest among non-Hispanic American Indian or Alaska Native women at 16.7 percent. Non-Hispanic white women's rate was 10.5 percent, followed by non-Hispanic black women at 6 percent, Hispanic women at 1.8 percent and non-Hispanic Asian women at 0.6 percent.
Those smoking rates, however, did not match the infant mortality rates between 2013 and 2015, according to a CDC report released in January. The infant mortality rate was highest among non-Hispanic black children at 11.3 percent, followed by American Indian-Alaska native at 8.3 percent, 5.0 percent among Hispanics, 4.9 percent among non-Hispanic white and 4.2 Asian/Pacific Islanders.
More educated woman were less likely to have smoked during pregnancy. At 12.2 percent, the rate was highest among women with a high school diploma or GED, followed by 11.7 percent among women without a high school degree. For women with some college or associate degree, the smoking rate waswas 7.9 percent, 1.0 percent for those with a bachelor's degree and 0.4 for women with a master's degree or higher.
"Identifying maternal characteristics linked with smoking during pregnancy can help inform the development of strategies to reduce the prevalence of maternal smoking and increase smoking cessation during pregnancy in the United States," the CDC said in its report.