Maternal smoking can have a negative impact on the child's reading skills and comprehension ability, according to a new study.
To analyze the link, lead author Dr. Jeffrey Gruen and his colleagues from Yale University looked at 5,000 children as part of the Avon Longitudinal Study of Parents and Children (ALSPAC).
All the children performed seven different tasks - reading speed, single-word identification, spelling, accuracy, real and non-word reading and reading comprehension.
Children who were highly exposed to nicotine (more than one pack of cigarettes per day) while in the mother's womb were found scoring 21 percent lower in all these tasks compared to children of mothers who abstained from smoking after conceiving.
Children exposed to nicotine are more likely to be ranked seven places lower in a class of 31, researchers said.
"It's not a little difference - it's a big difference in accuracy and comprehension at a critical time when children are being assessed, and are getting a sense of what it means to be successful," Gruen explained in a news release. "The interaction between nicotine exposure and phonology suggests a significant gene-by-environment interaction, making children with an underlying phonological deficit particularly vulnerable."
The results of the study have been published online in The Journal of Pediatrics.
Smoking during pregnancy brings many health problems for the child. Premature birth, low birth weight, cot death, asthma, infections, still birth and autism are some of the risks. However, nearly 14 percent of women in the country continue smoking, even after the confirmation of pregnancy.
Previous studies have found many risks associated with smoking during pregnancy. A team of Swedish researchers found exposure to tobacco in the womb increasing the risks of wheezing and asthma in preschool children.
In another study, researchers from the Behavior Evaluation and Measurement Research Centre (CRAMC) of the Rovira i Virgili University found maternal exposure to smoking, either active or passive, affecting the physiological, sensory, motor and attention responses of a newborn.
Researchers from Canada found maternal smoking contributing to childhood obesity.
