Objectives: In 1986, the state health departments of Colorado, Maryland, and Missouri conducted a federally-funded demonstration project to increase smoking cessation among pregnant women receiving prenatal care and services from the Women, Infants, and Children (WIC) program in public clinics.
Methods: Low-intensity interventions were designed to be integrated into routine prenatal care. Clinics were randomly assigned to intervention or control status; pregnant smokers filled out questionnaires and gave urine specimens at enrollment, in the eighth month of pregnancy, and postpartum. Urine cotinine concentrations were determined at CDC by enzyme-linked immunosorbent assay and were used to verify self-reported smoking status.
Results: At the eighth month of pregnancy, self-reported quitting was higher for intervention clinics than control clinics in all three states. However, the cotinine-verified quit rates were not significantly different.
Conclusions: Biochemical verification of self-reported quitting is essential to the evaluation of smoking cessation interventions. Achieving changes in smoking behavior in pregnant women with low-intensity interventions is difficult.