The newborn screening results of 1,310 children examined by Ortolani's and Barlow's manual test, as well as 2,587 children investigated by sonography, have been compared. Of the sonographically pathological hips (technique of Graf), 52.2% had no sign of instability. This was especially true in dysplastic and decentering hip joints, but was found to a smaller degree even in dislocated hips. As a result, twice as many abduction pillows were ordered during the second period. Sonography also detected joints that were immature at birth, but became worse during development (8.9% of hips labeled type 2a, after Graf). A total of 6.54% pathological hips were detected by newborn screening and follow-up of immature hips.