This study examined the effects of a smoking cessation intervention on
stages of change in 349 low-income pregnant women. At first prenatal
visit, women were randomized into experimental or usual care condition
and classified by stage of change: precontemplation, contemplation, p
reparation, or action. For each stage of change at the first prenatal
visit, the stage distributions of the experimental and usual care grou
ps were compared at the second and 36-week prenatal visits. Kruskal-Wa
llis tests revealed significant differences at the second visit in the
stage distributions by condition for subjects who were initially in p
recontemplation or in preparation. In each case, a greater proportion
of experimental than usual care subjects advanced through the stages.
The shift was not maintained at the 36-week visit.