Real-World Effectiveness of a Community-based Multicomponent Maternal Smoking Cessation Program in Preventing Low Birthweight Deliveries: Findings from the CTTP Cohort

Introduction: The effect of smoking cessation during pregnancy on preventing adverse birth outcomes has been shown in studies of US birth certificate data, and in other nations. There is a paucity of data to optimize community-based maternal tobacco cessation programs to improve birth outcomes. Our objective is to evaluate the real-world effectiveness of a multi-component, community-based maternal smoking cessation program in preventing adverse infant outcomes using components of known efficacy. Methods: The Comprehensive Tobacco Treatment Program (CTTP) was a state-funded maternal tobacco smoking cessation program serving pregnant women in San Bernardino County, California, the largest county in the contiguous US. CTTP used a 6-8 week behavioral intervention with components of known efficacy (i.e. incentives, biomarker testing, feedback, and motivational interviewing). We conducted a retrospective cohort study of the 1,402 pregnant women enrolled in CTTP during 2012-2019. We conducted a multivariable logistic regression analysis with adverse infant outcomes (premature birth (PTB), low birthweight (LBW), and NICU admission) as the dependent variables, abstinence achieved during (prolonged abstinence (PA) through weekly urinary cotinine tests) or after the program (self-reported point prevalence abstinence (PPA)) as the main effect exposures, and pertinent confounders. Results: We found that PA during the program significantly decreased the odds of LBW (OR [95% confidence interval (CI) = 0.67 [0.47, 0.96], p = 0.03), and this association remained for self-report of PPA at 2-4 months after the program (OR [95% CI] = 0.70 [0.54, 0.90], p = 0.006), and six months after the program (OR [95% CI] = 0.65 [0.47, 0.90], p = 0.01). Similar, albeit weaker, trends were found for PTB. In these models, older age, early trimester at enrollment, and African American/Black ethnicity also trended toward higher rates of LBW and PTB. Conclusions: Abstinence achieved during a multi-component behavioral smoking cessation intervention program using components of known efficacy significantly reduced low birthweight deliveries in a multi-ethnic population.