Tobacco smoke contains thousands of chemicals including nicotine, carbon monoxide, heavy metals, poly-aromatic hydrocarbons (PAHs) and others that harm health. Prenatal tobacco exposure, through active smoking or environmental tobacco smoke (ETS), is one of the most significant avoidable causes of maternal and child morbidity and mortality [2].

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Conditions associated with smoking include pre-term birth, fetal growth restriction, low birth weight, miscarriage, specific congenital malformations, childhood leukemia, reduced maternal fertility, adverse respiratory, neurological and cardiovascular effects, and infant death [2–10].

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The effects of ETS are similar and consistent although not as strong as for active smoking [11–14]. Health problems from prenatal exposure may manifest in childhood, with increased risk of impaired lung function, asthma, obesity, cognitive deficits and detrimental cardiovascular consequences [15–23].

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Epigenetic changes from in-utero exposure to tobacco have been detected in children [25], and prenatal smoking has been shown to influence smoking habits of future generations [26,27].

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