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

Abstract

The detrimental effects of cigarette use during pregnancy are well documented. Studies have shown that cigarette smoking while pregnant is associated with multiple adverse outcomes including: pre-term birth, placental abruption, placenta previa, fetal growth restriction, stillbirth, increased rate of birth defects, and increased risk of sudden infant death syndrome. Cotinine is the primary metabolite of nicotine and allows for measurement of active as well as passive exposure. Cotinine freely cross the placental barrier and maternal concentrations are closely correlated with newborn plasma levels. The aim of this study was to compare maternally reported rates of tobacco use to fetal umbilical cord blood cotinine levels at the time of delivery. A cross-sectional study was conducted on 172 patients. Patients were asked a single yes or no question in regards to their cigarette use during pregnancy. Cord blood was collected at the time of delivery and analyzed for serum concentrations of cotinine. Cotinine levels greater than 3.0 ng/mL were considered consistent with the use of tobacco or tobacco cessation products. Maternal self-reporting of tobacco use indicates a reported tobacco use rate of 27.3% and an actual use rate of 30.2%. The reported tobacco non-use rate was 72.7% and the actual non-use rate was 66.3%. The prevalence of tobacco use during pregnancy in our study was 30.2%, while the overall rate in the United States is reported to be 12.3%. Our findings indicate that self-reported smoking prevalence and verified umbilical cord blood cotinine levels at the time of delivery have excellent correlation (kappa=0.76). Compared to the national average our study group also had nearly double the rate of tobacco use. Due to the deleterious effects of cigarette use during pregnancy continued efforts to educate patients regarding cigarette cessation is of utmost importance as cessation of tobacco products will improve and promote maternal and fetal well-being.