The discrepancy between self-reported smoking status and urine continine levels among women enrolled in prenatal care at four publicly funded clinical sites.

The discrepancy between self-reported smoking behavior and actual urine cotinine values among prenatal patients at four municipally operated clinical sites was examined. Face-to-face interview and birth certificate information about smoking behavior during pregnancy was compared with laboratory urine cotinine values for 74 patients. Almost three of every four (73%) self-reported nonsmokers had continine values greater than 80 ng/mL; one-half (48%) had values exceeding 100 ng/mL.