Between 1956 and 1999, 132,601 living children were born in Malmö, and screened for neonatal instability of the hip. All late diagnosed patients have been followed and re-examined clinically and radiologically. During the first years of screening, less than five per 1,000 living newborn infants were treated. This figure increased to 35 per 1000 in 1980, but later diminished again to about six per 1,000 annually after 1990. The number of referred cases decreased from 45 per 1,000 in 1980 to between 10 to 15 per 1,000 from 1990. During the period of high rates of referral and treatment a larger number of paediatricians were involved in the screening procedure than during the periods with low rates of ferral and treatment. Altogether 21 patients (0.16 per 1,000) with developmental dislocation of the hip were diagnosed late, after one week. At follow-up, 18 were free from symptoms and 15 considered to be diologically normal.