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 certifi cate 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 cotinine values greater than 80 ng/mL; one-half (48%) had values exceeding 100 ng/mL. Self-reported prenatal smoking behavior seems to be an unreliable indicator of actual smoking status among low-income prenatal patients, resulting in missed opportunities to lower tobacco-related exposure/risk among women with the poorest birth outcomes.
Smoking during pregnancy represents one of the most significant, preventable causes of perinatal morbidity and mortality in the United States, including prematurity, low birth weight and sudden infant death syndrome.1–3 Findings from several clinical trials indicate that women who stop smoking can achieve birth outcomes similar to those of nonsmokers.4–7 Numerous studies reveal that minimum contact, relatively inexpensive, and ultimately cost-effective, health education interventions delivered by health care providers in prenatal care settings can signifi cantly increase the percentage of women who quit or reduce smoking during pregnancy.8 Because they are both low-cost and efficacious, these interventions could be widely adopted and thus have the potential to reduce the risks associated with tobacco smoke exposure during pregnancy on a large-scale basis.8,9
One largely unexplored barrier to the full realization of the benefits of prenatal smoking cessation/reduction methods is patient nondisclosure of smoking status.10 Although biochemical tests to determine concentrations of cotinine—the major metabolite of nicotine—in hair, blood, saliva, or urine are available, such tests are not done in most prenatal care settings. Providers typically rely on self-reported smoking behavior to assess the extent of a woman's direct exposure to tobacco smoke during pregnancy. However, the motivation on the part of patients to conceal or understate exposure from cigarette consumption, especially in light of the increasingly negative social connotations being attached to prenatal smoking, may be quite strong.8,11 The extent to which prenatal patients actually do conceal, or otherwise understate, cigarette consumption is, however, largely unknown. We designed this study to compare self-reported smoking behaviors with actual urine cotinine levels for women who enrolled for prenatal care at several publicly funded clinics operated by the Philadelphia Department of Public Health. Before this study, self-report had been the method used by these providers to assess smoking status and served as the sole mechanism for triggering cessation/reduction counseling interventions with prenatal patients.
David A. Webb, PhD, is Director of Research in Ambulatory Health Services, Philadelphia Department of Public Health, Pennsylvania.
Neal R. Boyd, EdD, MSPH, is a Professor in the Department of Prevention and Community Health, School of Public Health and Health Services, George Washington University, Washington, D.C.
Darlene Messina, BA, is a Senior Health Educator in Ambulatory Health Services, Philadelphia Department of Public Health, Pennsylvania.
Richard A. Windsor, PhD, MPH, George Washington University, Department of Prevention and Community Health, School of Public Health and Health Services, Washington, DC.
Corresponding author: David A. Webb, PhD, Philadelphia Department of Public Health, 500 S. Broad Street, Philadelphia, PA 19146 (e-mail: David.Webb@Phila.Gov).