Three hundred and twenty eight examined adult men and 346 examined adult women were macrosomic at birth (4000 g or over). The control group consisted of 564 adult men and 749 adult women with birth weights of 2500 to 3999 g. Both male and female macrosomic babies achieve greater weights and heights in adulthood than those in the control group. There are more overweight and obese men in the macrosomic group than in the control group and the same is true of the women (p < 0.001). The mean values of the BMI (body mass index) for the macrosomic adults are greater than those for the control group (p < 0.001). Fetal macrosomia is a good predictor of the weight and height of adult men and women.