Prenatal smoking among adolescents and risk of fetal demise before and during labor.

摘要

STUDY OBJECTIVE: To investigate the relationship between smoking during pregnancy and the occurrence of stillbirth phenotypes among adolescent mothers. DESIGN: Retrospective cohort SETTING: Singleton births in Missouri from 1978 through 1997. PARTICIPANTS: Two groups of "younger" (<15 years) and "older" (15-19 years) adolescent mothers were compared to "mature" mothers (age 20-24 years). MAIN OUTCOME MEASURES: Cox Proportional Hazards Regression models generated adjusted risk estimates of the association between intrauterine nicotine exposure and the risk of total, antepartum, and intrapartum stillbirth in each age group. RESULTS: Approximately 32% (N=205,887) of the total 633,849 singleton births analyzed were among adolescent mothers. The overall prevalence of smoking was 31.2%, with the lowest prevalence (14.1%) among the youngest mothers while older adolescents had the highest (31.7%). The risk for intrapartum stillbirth among smoking adolescents <15 years of age was twice the risk for older adolescent and mature mothers. The risk of intrapartum stillbirth among smokers decreased as maternal age increased: [adjusted hazard ratio (AHR), 95% confidence interval (CI) for young mothers: 4.0, 95%CI=0.6-28.7; for older adolescents AHR=1.5, 95%CI=1.1-2.1 and for mature mothers AHR=1.8, 95% CI=1.4-2.2], respectively. CONCLUSIONS: In utero tobacco exposure has maternal age-related differential and lethal effects on the fetus. Young maternal age tends to potentiate these effects. There is a public health need to develop appropriate smoking cessation messages targeted specifically to this high risk group.