Serum Cotinine Concentration and Self-reported Smoking during Pregnancy

Abstract

Although during pregnancy there is a better correlation between maternal serum cotinine concentration and adverse outcome than between self-reported smoking and such an outcome, few studies of pregnancy have measured cotinine concentration to determine how much a woman smokes. This study assessed the accuracy of self-reported smoking during pregnancy by performing serum cotinine assays on 448 women registered in the Collaborative Perinatal Project (1959-1966). Based on the assumption that a serum cotinine concentration of >10 ng/ml represented active smoking, 94.9% of women who denied smoking and 87.0% of women who stated that they smoked (kappa=0.83) reported their status accurately. Among smokers, the correlation coefficient between cotinine concentration and number of cigarettes smoked per day was 0.44. Serum cotinine concentration correlated more strongly than self-reported smoking with infant birth weight (r=0.246 vs. 0.200). In conclusion, this study showed that pregnant women accurately reported whether they smoked, but cotinine concentration was a better measure than self-report of the actual tobacco dose received.

Lower agreement on behavioral factors than on medical conditions in self-reported data among pregnant latina women

“…In previous studies that examined the accuracy of self-reported behaviors with drug test results among pregnant women, most have found fairly good agreement on usage with slight under-reporting of amount of alcohol consumption (10,11) or number of cigarettes smoked (23,24). In our study, we did not perform laboratory tests measuring drug levels for cigarette smoking or alcohol use and therefore could not assess validity.…”

Accelerated Metabolism of Nicotine and Cotinine in Pregnant Smokers

“…Among pregnant smokers, maternal levels of cotinine correlate better with outcome measures such as birth weight than the number of cigarettes smoked per day (Haddow et al, 1987;Mathai et al, 1990;Bardy et al, 1993;Li et al, 1993;Ellard et al, 1996;Klebanoff et al, 1998;SeckerWalker et al, 1998). Recently, a study of women during pregnancy and again postpartum found that during pregnancy the median saliva cotinine concentration per cigarette was 3.5 ng/ml versus 9.9 ng/ml when not pregnant (Rebagliato et al, 1998).…”

Self-Reported Tobacco Use and Correlation with Umbilical Cord Blood Cotinine levels at Delivery among Appalachian Gravidas

“…A study of 448 women using a maternal serum cotinine concentration of >10.0 ng/mL to define tobacco users determined that 94.9% of women who denied smoking and 87.0% of women who stated they smoked reported their status accurately (kappa=0.83). 14 Kvalvik et al studied a subsample of 2,997 women in the Norwegian Mother and Child Cohort Study (MoBa) to assess selfreported tobacco use and plasma cotinine concentrations at 18 weeks gestational age using a cutoff of 12ng/mL. 15 The sensitivity and specificity for self-reported smoking was 82% and 99% respectively.…”