Smoking during pregnancy and newborn neurobehavior.
OBJECTIVE
This was a prospective study of the effects of maternal smoking during pregnancy on newborn neurobehavior, including dose-response relationships using self-report and a bioassay of nicotine exposure.


METHODS
The sample included 27 nicotine exposed and 29 unexposed full-term newborn infants with no medical problems from comparable social class backgrounds. Mothers were excluded for using illegal drugs during pregnancy, using antidepressant medication, or if they consumed >3 alcoholic drinks per month. Nicotine exposure was determined by maternal self-report and cotinine in maternal saliva. The NICU Network Neurobehavioral Scale (NNNS) was administered by masked examiners in hospital to measure neurobehavioral function. NNNS scores were compared between nicotine-exposed and -unexposed groups including adjustment for covariates. Dose-response relationships with NNNS scores were computed for maternal salivary cotinine and maternal report of number of cigarettes per day during pregnancy.


RESULTS
After adjustment for covariates, the tobacco-exposed infants were more excitable and hypertonic, required more handling and showed more stress/abstinence signs, specifically in the central nervous system (CNS), gastrointestinal, and visual areas. Dose-response relationships showed higher maternal salivary cotinine values related to more stress/abstinence signs (r =.530) including CNS (r =.532) and visual stress (r =.688) and higher excitability scores (r =.617). Cigarettes per day during pregnancy was related to more stress/abstinence signs (r =.582) including CNS (r =.561) and visual stress (r =.640).


CONCLUSIONS
These findings suggest neurotoxic effects of prenatal tobacco exposure on newborn neurobehavior. Dose-response relationships could indicate neonatal withdrawal from nicotine. Research directed at understanding the effects of cigarette smoking during pregnancy on infants can lead to improved public health outcome.
Law
Karen L
KL
Brown Medical School, Providence, Rhode Island, USA.
Stroud
Laura R
LR
LaGasse
Linda L
LL
Niaura
Raymond
R
Liu
Jing
J
Lester
Barry M
BM
D000293:Adolescent; D000328:Adult; D002490:Central Nervous System / Q000187:drug effects; D002657:Child Development / Q000187:drug effects; D003367:Cotinine / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D005314:Embryonic and Fetal Development / Q000187:drug effects; D005260:Female; D006801:Humans; D018730:Infant Behavior / Q000187:drug effects / Q000523:psychology; D007231:Infant, Newborn; D018811:Maternal Exposure / Q000009:adverse effects; D008431:Maternal-Fetal Exchange / Q000187:drug effects; D009035:Mothers / Q000145:classification; D009357:Neonatal Abstinence Syndrome / Q000175:diagnosis / Q000209:etiology; D009538:Nicotine / Q000009:adverse effects; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D012463:Saliva / Q000737:chemistry; D012650:Self Disclosure; D012907:Smoking / Q000009:adverse effects*
D009538:Nicotine; D003367:Cotinine