Hip screening is recommended for early detection of hip dysplasia; however, the strategy and efficacy were questioned. We performed ultrasonography to objectively observe the hip development in a group of infants and raise reflections on the efficacy of newborn ultrasonographic hip screening. A total of 1333 newborns (705 male and 628 female) received hip ultrasonography in the first week after birth. Clinical hip instability was detected by the Ortolani test. Hip dysplasia was defined by ultrasonography. A second survey of 90 babies was performed 1 month later on the babies with clinical hip instability or ultrasonographic Graf's type IIa, IIc, D, III, and IV hips. All the hip ultrasonographies were performed by the same investigator. Clinical instability was detected in 13 hips of 10 babies. Manual tests helped to detect unstable hips that had worse ultrasonographic measurements than those stable hips. Five Graf's type IIc hips and four type III hips were detected from the 2666 hips. At the age of 1 month, eight of the nine Graf's type IIc or III hips attained physiological status without treatment. A strong trend of spontaneous resolution in clinical hip instability and ultrasonographic dysplasia was observed in the newborns. The results did not support immediate treatment on the basis of newborn manual or ultrasound hip screening. We recommend manual testing in the newborn nursery to detect the hips at risk of dysplasia and ultrasonography after the first month after birth to confirm the diagnosis and judge the management.