Within this group, 53% (10/19) of those who tested positive at intake also tested positive at FAP. Within the group where both intake and FAP specimens were available, of the 20 that ever tested drug positive, half showed the same usage at both timepoints (eight positive for THC, one for both THC and opioids, and one for benzodiazepines). Additionally, one woman tested customer reviews positive for cocaine and opioids, and another for THC, at FAP but not intake. Seven women tested positive for THC at intake, but not at FAP. Effects of Drug Use on Smoking Cessation No significant differences were found in smoking abstinence rates between those who ever versus never tested drug positive across the two assessments (CMH ��2 (1) = 0.07, p = .79) or at FAP (CMH ��2 (1) = 2.78, p = .10).

There was no evidence that the effect of drug use on smoking abstinence was heterogenic across treatment groups at any time during pregnancy (Breslow�CDay ��2(1) = 0.33, p = .57) or at FAP (Breslow�CDay ��2(1) = 0.77, p = .38). Although differences in smoking abstinence for those testing drug-positive at FAP is not significant, 72% (13/18) of those who tested positive for drug use at the FAP assessment were also positive for cotinine (i.e., recent cigarette smoking) as compared with 51% (28/55) of those testing drug negative. CONCLUSIONS The present results demonstrate that illicit drug use, especially marijuana, is common in a sample of pregnant women enrolled in smoking-cessation treatment. The approximately 30% prevalence rate for marijuana use in this study corresponds well with the 23% of pregnant smokers reporting use in the last month in a U.

S. national survey of drug use (SAMHSA, 2010) and is considerably higher than the 2%�C4% of pregnant women in general who report marijuana use (e.g., Havens, Simmons, Shannon, & Hansen, 2009). Additionally, the majority of women who tested positive for illicit drug use at the beginning of their pregnancy in this study also tested positive near the end of their pregnancy, suggesting ongoing use. It should be noted that our measurements of drug use likely underestimate illicit use in pregnant smokers, as those who were receiving opioid-maintenance therapy (buprenorphine or methadone) were excluded from the current trials as opioids are known to alter smoking rates (e.g., Mello, Mendelson, Sellers, & Kuehnle, 1980).

As opioid-maintained pregnant smokers have relatively high rates of illicit drug use (Choo, Huestis, Schroeder, Shin, & Cilengitide Jones, 2004; Haug, Stitzer, & Svikis, 2001; Jones et al., 2009), any trial that excludes them will likely underestimate illicit drug use in pregnant smokers. One concern about drug use during pregnancy is possible detrimental effects on smoking cessation. While this study was not powered to investigate effects on treatment success, many abused drugs are known to increase smoking rates (e.g.