Participant characteristics, by group assignment
| Control (n=144) | Intervention (n=133) | Total | |
| White1-150 | 75% | 85% | 80% |
| Married or living with partner | 67% | 62% | 64% |
| Completed high school | 65% | 64% | 65% |
| Completed college | 10% | 7% | 8% |
| Birth was first live birth after 20 weeks | 62% | 61% | 61% |
| Mean (SD) age | 25.2 (6.0) | 24.0 (5.3) | 24.6 (5.7) |
| Mean (SD) number of cigarettes smoked per day before pregnancy | 11.8 (8.0) | 12.5 (8.2) | 12.1 (8.1) |
| Husband/partner smokes | 43% | 50% | 46% |
| Very confident to remain a non-smoker | 64% | 66% | 65% |
↵1-150 χ2 = 4.25, p = 0.04.