There has been considerable interest in the possibility that prenatal events could influence the adult life. Adults who were small at birth have been reported to have higher blood pressure and increased risk of death from ischaemic heart disease, although there are some contradictory results. The aim of the present study was to determine the association between size at birth and later risk factors (hypertension, hyperinsulinism, hyperglycaemia and dyslipidaemia) in prepubertal children. The authors examined 205 children (121 boys, 84 girls) at the age of 6-10. They compared children born full term with normal weight, height and head circumference (1st group), the children born full term with birthweight, height and head circumference less than 10th centile (2nd group), children born full term with birthweight less than 10th centile and with normal length and head circumference (3rd group) and children who were preterm at birth (4th group). The age of children at the time of investigation was comparable in the four groups. Weight and height of the children in the 2nd group were significantly lower than in the 1st and 4th groups (2nd group vs 4th group: p < 0.01; 2nd group vs 1st group: p < 0.001). Dyslipidaemia was found 21% in the 1st group, 17% in the 2nd group, 16% in the 3rd group and 28% in prematures. The mean of the systolic and diastolic blood pressures were similar in the four groups. Hypertension was 12.5% in the 1st and 3rd groups, 5.6% in the 2nd group and 8.9% among prematures. According to the results cardiovascular risk factors can not be proved among children at the age of 6-10 who were born with low birthweight. Further studies are required to determine whether which stage of pregnancy might influence birthweight and later risk factors.