"• The annual average rate of past month cigarette use in 2012 and 2013 among women aged 15 to 44 who were pregnant was 15.4 percent (Figure 4.5). The rate of current cigarette use among women aged 15 to 44 who were pregnant was lower than that among women who were not pregnant (24.0 percent). This pattern was also evident among women aged 18 to 25 (21.0 vs. 26.2 percent for pregnant and nonpregnant women, respectively) and among women aged 26 to 44 (11.8 vs. 25.4 percent, respectively). Rates of current cigarette use in 2012-2013 among pregnant women aged 15 to 44 were 19.9 percent in the first trimester, 13.4 percent in the second trimester, and 12.8 percent in the third trimester.
"• The annual average rates of current cigarette use among women aged 15 to 44 who were not pregnant decreased from 30.7 percent in 2002-2003 to 24.0 percent in 2012-2013 (Figure 4.5). However, the prevalence of cigarette use among pregnant women in this age range did not change significantly during the same time period (18.0 percent in 2002-2003 and 15.4 percent in 2012-2013)."

Source

Substance Abuse and Mental Health Services Administration, Results from the 2013 National Survey on Drug Use and Health: Summary of National Findings, NSDUH Series H-48, HHS Publication No. (SMA) 14-4863. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2014.