Abstract
Left-handedness has been suggested as a sensitive marker of neurotoxic exposures or of the hormonal environment in fetal life. The prevalence of left-handedness was the subject of a follow-up study in children aged 5 to 9 years and correlated to exposures recorded by their mothers during pregnancy. Altogether 965 children were studied by means of questionnaires completed by the mothers. The response rate was 91%. Smoking, head circumference, Apgar score and indicators of fetal growth retardation were found not to be associated with increased prevalence of left-handedness.