Smoking during pregnancy affects neurodevelopment in babies

Washington - Newborns exposed to nicotine from both active and passive smoking mothers show poor physiological, sensory, motor and attention responses, a new study has shown.

Smoking during pregnancy has been linked to many different problems in infants like learning difficulties, attention deficit disorder with hyperactivity and even obesity.

However, although the paediatric and obstetric disorders linked to tobacco during this stage are well defined, the effects on neonatal behaviour have not yet been studied in depth.

The new study headed by experts at the Behaviour Evaluation and Measurement Research Centre (CRAMC) of the Rovira i Virgili University goes further and analyses the effects of passive smoking during pregnancy on the newborn.

The scientists evaluated the behaviour of 282 healthy newborns using the Neonatal Behavioural Evaluation Scale. This allows for interaction with the newborn in order to evaluate its behaviour and responses between 48 and 72 hours after birth.

From those mothers studied, 22 percent smoked during pregnancy and hardly 6 percent were exposed to passive smoking. Out of the smoking mothers, 12.4 percent had between 1 and 5 cigarettes a day; 6.7 percent had between 6 and 10 a day; and 2.8 percent had between 10 and 15 a day.

None of them smoked more than 15 cigarettes a day.

“Newborns who have had intrauterine exposure to nicotine, whether in an active or passive way, show signs of being more affected in terms of their neurobehavioural development. This could be an indicator of pathologies, independently of sociodemographic, obstetric and paediatric factors,” Josefa Canals and Carmen Hernandez, the lead authors of the study, told SINC.

The results reveal that those born to smoking and passive smoking mothers score low in their ability to inhibit stimuli that could alter the central nervous system.

Furthermore, children of passive smoking mothers have poor motor development and those of smoking mothers have less ability to regulate behaviour and response in physiological, sensor, motor and attention terms.

The study has been published in the Early Human Development journal.