Cross-sectional studies of physical growth in twins. Postmature and small-for-dates children.

From 16955 live births which occurred throughout the United Kingdom in April 1970, three groups of children who might have suffered from fetal malnutrition, i.e. the multiple, postmature and small-for-dates births were selected with a 10% random sample. Their birthweights and weights, heights and head circumference measurements were compared at the ages of 22 months and 3 1/2 years. Differences between the random and postmature groups still present at 22 months disappeared at 3 1/2 years. Variations in the other groups persisted and the compensation occurring at 22 months had apparently ceased at 3 1/2 years. The three examinations were linked and the children including those in the control group showed considerable mobility in their quartile ratings. Only a minority remained unchanged. At the same time the weights of the heavier and lighter children tended to go towards the mean. As the velocity of growth slowed the redistribution tended to lessen but was still taking place at the age of 3 1/2 years.