Reducing fetal origins of childhood obesity through maternal smoking cessation during pregnancy: an intervention study.

Rapid infant weight gain predicts childhood obesity. We aimed to estimate effect size and identify critical timing for intervention-assisted smoking cessation during pregnancy to impact infant weight gain. We followed 25 mother-infant dyads in the UB Pregnancy and Smoking Cessation Study (Buffalo, NY, USA). Maternal smoking status was biochemically verified and monitored through pregnancy. Birth weight and length were extracted from birth records. Research staff measured infant weight and length at 2 weeks and monthly from 1 to 12 months of age. Mixed models were used to fit infant BMI-for-age z-score (ZBMI) trajectories. We found infants of quitters had lower ZBMI gain from birth to 12 months (mean ± SD, 1.13 ± 1.16) than infants of persistent smokers (2.34 ± 1.40; p = 0.035), with Cohen's d effect size being large (0.96). The infant ZBMI gain from birth to 12 months was low (<0.47) if smoking cessation was initiated between 15 and 27 weeks of pregnancy, but started to increase if quitting at 28 weeks (0.65) and accelerated with time (e.g., 3.16 if quitting at 36 weeks). We concluded maternal smoking cessation during pregnancy may reduce fetal origins of obesity through reducing infant weight gain, especially if quitting smoking by 27 weeks of pregnancy.

A multicomponent behavioral intervention for smoking cessation during pregnancy: a nonconcurrent multiple-baseline design.

Given serious consequences of maternal smoking, we aimed to develop and test a multicomponent behavioral intervention to enhance smoking cessation during pregnancy. In this nonconcurrent, multiple-baseline intervention pilot study, 48 daily smoking pregnant women (mean 13.7 weeks of gestation) were recruited from Buffalo, NY, USA. Upon completion of the repeated baseline smoking monitoring (up to 3 weeks), 30 continuous smokers received a contingent financial incentive-based intervention with three additional components (education and counseling, monitoring and feedback, and family support). After the quit date, participants met with counselors (~1 hr/visit) daily for 2 weeks and twice a week for another 6 weeks. Twenty-one out of 30 participants quit smoking completely (verified by urine cotinine) after receiving the intervention, and the other nine nonquitters decreased smoking substantially. The estimated smoking cessation rate was 70.0% (21/30) at the second week of the intervention, and 63.3% (19/30) at the conclusion of the 8-week intervention assuming the dropouts as smoking. In interrupted time series analysis, the mean daily number of cigarettes smoked among quitters decreased by 6.52, 5.34, and 4.67 among early, delayed, and late intervention groups, respectively. Quitters' mean urine cotinine level maintained stably high before the intervention but decreased rapidly to the nonsmoking range once the intervention was initiated. Most participants (85.7%) reported meeting or exceeding expectations, and 100% would recommend the program to others. This pilot multicomponent intervention was feasible and acceptable to most participants, resulting in a high smoking cessation rate among pregnant smokers who were unlikely to quit spontaneously.