Nicotine in pregnancy could have long term effects in children even upto  adolescence confirms a study.

Team@CMHF

The maternal use of tobacco while pregnant is associated with an increased risk for psychotic symptoms such as hallucinations and delusions in their children, with evidence of a dose-response effect, according to results from a large cohort study
“These findings indicate that the risk factors for development of non-clinical psychotic experiences may operate during early development,” write Stanley Zammit, PhD, clinical senior lecturer in psychiatric epidemiology in the Department of Psychological Medicine at Cardiff University in Wales and the University of Bristol in the United Kingdom, and colleagues.
“This is the only study to really try and tease out to what extent this association is causal rather than being confounded or explained by other factors,” Dr. Zammit told Medscape Psychiatry.
“There could still be confounding, of course, but this makes us a bit more confident that the association may be due to the effects of nicotine on the developing brain in the uterus,” he added.
Smoking While Pregnant Common in the United Kingdom
“In the [United Kingdom], 15-20% of women continue to smoke throughout their pregnancy, and although cannabis use is less common, some alcohol intake during pregnancy is reported by most women,” write the study authors.
Maternal Tobacco Use Increased Risk for PLIKS
At the end of this cohort study, a total of 734 of the children (11.6%) were rated as having suspected or definite PLIKS, and 300 of these children (4.7%) had definite symptoms.
The investigators found that maternal tobacco use during pregnancy was strongly associated with an increased risk for suspected or definite PLIKS in their offspring (
Future Studies Needed
“Maternal smoking during pregnancy was associated with an increased risk of psychotic symptoms in the children, with evidence of a dose-response effect whereby risk of PLIKS was highest in the offspring of mothers who smoked most heavily,” write the study authors.
“If our results are non-biased and truly reflect a causal relationship, we can estimate that about 20% of adolescents in this cohort would not have developed psychotic symptoms if their mothers had not smoked,” they add.
“Hopefully this will encourage more research into the effects of tobacco on brain development in utero, and increase understanding of how any disruptions of brain development can impact risk of psychosis,” Dr. Zammit concluded.
In the Avon Longitudinal Study of Parents and Children cohort, frequency of maternal tobacco use during pregnancy was linked to a greater risk for suspected or definite psychotic symptoms occurring in the offspring at age 12 years, suggesting a dose-response effect.
The association of maternal alcohol use with psychotic symptoms was seen almost exclusively in the offspring of women drinking more than 21 units weekly. Maternal use of cannabis was not associated with any detectable increased risk for psychotic symptoms in the offspring, but statistical power was limited

Ref: http://www.medscape.org/viewarticle/710668