Smoking during pregnancy and vision difficulties in children: a systematic review

Cigarette smoking during pregnancy is a major public health concern. Intra-uterine exposure to maternal cigarette smoking is associated with increased risks of growth and neurodevelopmental problems during childhood and later life. Few studies have focussed on visual difficulties in children in the context of maternal smoking during pregnancy. A systematic search of online databases was carried out between February and May 2013 to examine the trend in visual outcomes in children exposed to maternal cigarette smoking during intra-uterine life. Twenty-four non-randomized studies were identified. Each study was rated for quality using the Newcastle-Ottawa Scale. Most studies (n=18) reported fetal exposure to active or passive maternal cigarette smoking to be associated with an increased risk of adverse visual outcomes in children. In particular, there were higher rates of strabismus, refractive errors and retinopathy among children of women who smoked during pregnancy. These findings suggest that fetal exposure to cigarette smoke is a significant risk factor for visual problems during later life and that certain visual faculties, such as the intraocular muscles and retinal neurons, are more affected than others. The findings provide evidence in support of public health policies aimed at reducing fetal exposure to smoking by advising both women and their partners to quit smoking during pregnancy.