The objective of this study is to test the effect of smoking cessation in pregnancy or in lactation on preventing rapid infant adiposity gain. Investigators propose a randomized, controlled experiment among smoking pregnant women from 1st prenatal care visit through 6 months of postpartum period. Two-phase randomization will be applied to separate the effects of smoking cessation in two different critical periods (i.e., pregnancy and lactation) on infant adiposity gain. Investigators will first randomly assign 40 smoking pregnant women into either the multicomponent intervention (N=30) or the education-only control group (N=10). The multicomponent intervention group will receive education and counseling, monitoring and feedback, contingent financial incentives, and family support, while the control group will receive education only. At the end of pregnancy, investigators will further randomize successful quitters (estimated N=20) from the multi-component intervention group into either the continuous multi-component intervention group in lactation (N=10) or the education-only control group (N=10). All women and their newborns will be followed from enrollment to 6 months postpartum. The key outcomes include maternal smoking abstinence confirmed by urine-cotinine and infant gain in weight-for-length z-score. Specific Aim 1 is to examine the effects of maternal smoking cessation intervention in pregnancy on infant gain in weight-for-length z-score from birth to 6 months. Specific Aim 2 is to examine the effect of maternal smoking abstinence intervention in lactation and infant post-weaning gain in weight-for-length z-score among the women who have successfully quit smoking in pregnancy.

The objective of this study is to test the effect of smoking cessation in pregnancy or in lactation on preventing rapid infant adiposity gain. Investigators propose a randomized, controlled experiment among smoking pregnant women from 1st prenatal care visit through 6 months of postpartum period. Two-phase randomization will be applied to separate the effects of smoking cessation in two different critical periods (i.e., pregnancy and lactation) on infant adiposity gain. Investigators will first randomly assign 40 smoking pregnant women into either the multicomponent intervention (N=30) or the education-only control group (N=10). The multicomponent intervention group will receive education and counseling, monitoring and feedback, contingent financial incentives, and family support, while the control group will receive education only. At the end of pregnancy, investigators will further randomize successful quitters (estimated N=20) from the multi-component intervention group into either the continuous multi-component intervention group in lactation (N=10) or the education-only control group (N=10). All women and their newborns will be followed from enrollment to 6 months postpartum.The key outcomes include maternal smoking abstinence confirmed by urine-cotinine and infant gain in weight-for-length z-score. Specific Aim 1 is to examine the effects of maternal smoking cessation intervention in pregnancy on infant gain in weight-for-length z-score from birth to 6 months. Specific Aim 2 is to examine the effect of maternal smoking abstinence intervention in lactation and infant post-weaning gain in weight-for-length z-score among the women who have successfully quit smoking in pregnancy.

Inclusion Criteria:

1. Able to read, understand, and speak English.
2. Are 18-39 years old
3. Are less than 20 weeks of gestation
4. Have a singleton pregnancy
5. Currently smoking one or more cigarettes per day, based on self-report.
6. Currently smoking biochemically verified by a level of 1 or higher in urine cotinine test (i.e., >100ng/mL cotinine concentration).
7. Willing to try to quit or reduce smoking by behavioral intervention
8. Willing to monitor smoking status by breath carbon monoxide and saliva cotinine.
9. Willing to provide breath, saliva, and urine samples to test smoking status
10. With low household income (meeting federal income eligibility guidelines for the Special Supplemental Nutrition Program for Women, Infants, and Children) and/or low education level (≤12 years). These disadvantaged pregnant women are very likely not to quit spontaneously, and thus need extra intervention most.
11. Currently living in Erie County or Niagara County; don't plan to move out of these two counties during the current pregnancy.

Exclusion Criteria:

1. Previous history of major chronic disease or blood clotting disorders such as cancer, thyroid disorders, heart disease, kidney disease
2. Depression or have been diagnosed with depression or post-partum depression at any time
3. In treatment for Axis 1 disorders that prevent them following smoking cessation interventions