The incidence of the cremasteric reflex in normal boys.

The presence or absence of the cremasteric reflex was documented in 225 normal male subjects ranging in age from birth to 12 years. The reflex was initiated by stroking the skin of the inner aspect of the thigh. The cremasteric reflex was present in 48 of 100 newborns (48%), 32 of 71 subjects (45%) between 1 and 30 months old, and all 54 boys older than 30 months. The presence of the cremasteric reflex may be clinically significant in boys with suspected cryptorchidism or acute scrotal inflammation.