The impact of motivational interviewing on behavior stages of nulliparous pregnant women preparing for childbirth: a randomized clinical trial.

Objective: To examine the effectiveness of motivational interviewing (MI) on the stages of behavior change among nulliparous pregnant women who were preparing for childbirth.Methods: In this randomized clinical trial, 234 pregnant women were studied in two intervention groups (MI and lecture), and one control group at three stages. In weeks 16-19 of pregnancy, two counseling sessions were held for the MI group, and one lecturing session was held for the lecture group. In weeks 21 and 37 of pregnancy, the three groups were reevaluated.Results: At baseline, more than 70% of women were at pre-contemplation and contemplation stages. In week 21 of pregnancy, in MI 71% were at preparation stage, whereas in the lecture and control groups, 51.9% and 49.4% were at the contemplation stage, respectively. In week 37 of pregnancy, in MI, lecture and control groups, 90%, 59.7% and 27.3% were at the action stage, respectively (p<.001). The result of generalized estimating equation (GEE) analysis using a Poisson model indicated that the incident rate for lecture group was 1.7 (95% CI: 1.2-2.5) times the incident rate for the MI group. Also, the incident rate for control group was 3.4 (95% CI: 2.2-5.0) times the incident rate for the MI group.Conclusions: Motivational interviewing was effective in guiding nulliparous mothers toward positive behavior stages.