Effects of maternal smoking during pregnancy on newborn neurobehavior: neonatal nicotine withdrawal syndrome.

Abstract

To the Editor. — We read with great interest the paper of Law et al1 wherein the effects of maternal smoking on newborn neurobehavior was investigated. The authors compared 29 and 27 newborns unexposed and exposed to maternal smoking, respectively. A mean of 6.7 cigarettes per day was declared by smoking mothers during pregnancy. Mean maternal salivary cotinine, obtained only in 16 cases (3 of which showed a zero value), was 32.9 ng/mL. Newborn neurobehavioral function was measured by the NICU Network Neurobehavioral Scale within 48 hours after birth.1 The authors disclosed neurotoxic effects of prenatal tobacco exposure, suggesting a likely neonatal withdrawal syndrome. In the studies by our team,2,3 we already postulated the existence of a neonatal nicotine withdrawal among newborns exposed to cigarette smoke. The Finnegan clinical score4 was used in 50 newborns from smoking mothers to evaluate the withdrawal syndrome together with the measure of newborn urinary cotinine as a biomarker of acute exposure to tobacco smoke5 and neonatal hair nicotine detection to verify a chronic exposure to cigarette constituents during the entire fetal life. No definitive positive result for defining a withdrawal syndrome by means of the Finnegan test (2 consecutive scores >8) was registered. However, scores between 0 and 8, especially by irritability and tremor over the first 24 hours of life, were recorded in 17 newborns. All these newborns, from mothers who smoke >20 …