161 Prenatal Nicotine Exposure Increases the Risk of Neonatal Apnea -A National Birth-Cohort Study

Abstract

Background: Smoking during pregnancy is associated with disturbed cardio-respiratory control of the infant and is a major risk factor for sudden infant death syndrome (SIDS). Although it is not known whether the harmful effects of smoking are caused by nicotine or other toxic substances in tobacco smoke, nicotine replacement therapy (NRT) during pregnancy is often regarded as being safer than smoking.Aim of study: To investigate if the disturbances in cardio-respiratory control seen in infants exposed to smoke are also noticed in infants exposed to nicotine (in the form of snuff) prenatally.Method: We conducted a population-based cohort study in the Swedish Medical Birth Register, 1999-2006, to study the association between maternal tobacco use and neonatal apnea.Of 569,859 newborns, 7,599 were born to snuff-using mothers, 41,391 and 16,928 born to light smokers (1-9 cig./day) and heavy smokers (≥10 cig./day), respectively. Apnea was defined by using ICD-10 codes P28.2-P28.4. Logistic regression was used for statistical analysis.Results: Compared with infants to non-users, prenatal exposure to snuff doubled the risk of apnea, and this risk was not confounded by maternal or neonatal characteristics (OR 1.97; CI [1.30-2.98]). In contrast, the smoking-related increased risk of apnea was no longer significant after adjustment for gestational age.Conclusion: Prenatal nicotine (snuff) is associated with a higher risk of neonatal apnea than smoking. This implies that it is not safe to recommend nicotine replacement therapy (NRT) for smoking cessation during pregnancy.