A series of some 1,700 newborn infants has been examined in order to discover the frequency of undescended testicle, and to find out what happened to the testicle in those infants who had the deformity.

The incidence of undescended testicle in full-term infants at birth was 4 per cent.

Of fifty-five infants followed up, descent occurred within the first three months in the majority. After three months, descent was slow and appeared to be incomplete. At the end of one year seven infants remained in whom no descent had taken place.

The close similarity between the incidence of the condition in infants 1 year old and in adults has been discussed. Evidence from these observations on infants suggests that complete descent of the testicle does not occur after 3 months of age in the full-term infant.