Despite significant population level declines, smoking during pregnancy remains a major public health issue in the United States (US). Approximately 360,000–500,000 smoke-exposed infants are born yearly, and prenatal smoking remains a leading modifiable cause of poor birth outcomes (e.g. birth < 37 gestational weeks, low birth weight, perinatal mortality). Women who smoke during pregnancy are more likely to be younger and from disadvantaged socioeconomic and racial and ethnic groups, with some US geographic regions reporting increased prenatal smoking rates since 2000. Such disparities in maternal prenatal smoking suggests some pregnant women face unique barriers to cessation. This paper reviews the current state and future direction of smoking cessation in pregnancy in the US. We briefly discuss the etiology of smoking addiction among women, the pathophysiology and effects of tobacco smoke exposure on pregnant women and their offspring, and the emerging issue of electronic nicotine delivery systems. Current population-based and individual smoking cessation interventions are reviewed in the context of pregnancy and barriers to cessation among US women. Finally, we consider interventions that are on the horizon and areas in need of further investigation.

Background: We developed summaries of oral bottle-feeding skills among preterm (37 gestational weeks) infants using a mechanical device (Orometer) to measure intraoral pressure changes, with accompanying automated software and analytics. We then compared the rates of change in feeding skills over several weeks (feeding trends) between preterm and full-term infants. We also compared group means at 40 weeks postmenstrual age (PMA). Patients and methods: Healthy full-term and preterm infants capable of oral feeding were recruited from the Pediatric Outpatient Clinic at University of California, San Francisco, Fresno, and from the Oregon Health & Science University Doernbecher Neonatal Critical Care Unit, respectively. Feeding skill was quantified using an Orometer and automated suck-analysis software. Factor analysis reduced the >40 metrics produced by the Orometer system to the following seven factors that accounted for >99% of the sample covariance: suck vigor, endurance, resting, irregularity, frequency, variability, and bursting. We proposed that these factors represent feeding skills and that they served as the dependent variables in linear models estimating trends in feeding skills over time for full-term and preterm infants (maturation). At similar to 40 weeks PMA, we compared mean feedings skills between infants born preterm and those born full-term using predictions from our models. Results: Feeding skills of 117 full-term infants and 82 preterm infants were first captured at mean PMA of 42.3 and 36.0 weeks, respectively. For some feeding skills, preterm and full-term infants showed different trends over time. At 37-40 weeks PMA, preterm infants took similar to 15% fewer sucks than infants born full-term (P=0.06) and generally had weaker suck vigor, greater resting, and less endurance than full-term babies. Preterm infants' feeding skills appeared similar to those of full-term infants upon reaching >= 40 weeks PMA, although preterm infants showed greater variability for all factors. Conclusion: The Orometer device, accompanying software, and analytic methods provided a framework for describing trends in oral feeding, thereby allowing us to characterize differences in maturation of feeding between healthy preterm and full-term infants.

The association of co-occurring prenatal stress and tobacco exposures on childhood wheezing and asthma are not well established. In this study, we compared maternal prenatal hair cortisol concentration (HCC) to the maternal report of infant wheezing (y/n) in the first year of life among mother–infant dyads exposed to tobacco smoke and socioeconomic adversity. Data were obtained from the Vitamin C to Decrease Effects of Smoking in Pregnancy on Infant Lung Function study. Maternal adversity was defined by the level of education, household income, and health insurance provider. Hair was collected at delivery, representing average circulating third-trimester cortisol levels. HCC was log transformed and dichotomized into high/low cortisol groups that were placed into a multivariate model predicting wheeze. Subjects (n = 132) were primarily White with ≤high school education and receiving government-provided health insurance. Forty-five percent of infants wheezed. Average HCC was 3.39 pg/mg hair. Women with HCC > 3.55 pg/mg were more than twice as likely to report having a child who wheezed (odds ratio 2.56, 95% confidence interval 1.22–5.40; p = 0.01), adjusting for insurance provider and maternal asthma. Among this sample of dyads with prenatal smoke exposure, elevated maternal HCC was associated with child wheeze that was not diminished after consideration of covariates.

Study Design: Prospective Observational Propensity Score. Objectives: Randomization may lead to bias when the treatment is unblinded and there is a strong patient preference for treatment arms (such as in spinal device trials). This report describes the rationale and methods utilized to develop a propensity score (PS) model for an investigational device exemption (IDE) trial (NCT03115983) to evaluate decompression and stabilization with an investigational dynamic sagittal tether (DST) vs decompression and Transforaminal Lumbar Interbody Fusion (TLIF) for patients with symptomatic grade I lumbar degenerative spondylolisthesis with spinal stenosis. Methods: Twenty-five baseline covariates were selected for their expected relationship to patient outcomes or enrollment bias. Subclassification by PS quintiles was used to design a sample of investigational DST patients and TLIF controls with excellent covariate balance in which to estimate causal treatment effects. Additionally, balance in PS covariates was compared to available matching covariates from seven randomized spine IDE trials. Results: The PS subclassification design resulted in excellent balance across baseline covariates, as evidenced by small standardized mean differences and no significant between group differences after accounting for the PS design (all P ≥ 0.768). Differences in SMDs among covariates of randomized spine IDE trials were not significant ( P = 0.396). Conclusion: The PS subclassification design achieved excellent covariate balance between DST investigational and TLIF control participants. This PS designed sample shows covariate balance similar to that observed in published studies in which patients were randomized to investigational or control arms. Clinical trial registered with https://www.clinicaltrials.gov (NCT03115983).