S.W.
Hi,
My daughter also had hip dysplasia diagnosed at birth. We went to Orthopedic Center of the Rockies when she was two weeks old and saw Dr. Sobel, who is great. He put her in a Wheaton-Pavlic harness, which is a soft harness that velcros together around the legs and chest. It was adjustable as she grew and she could still move her legs and kick a liitle while in the correct position. Eventually she only had to wear it at night and it could be washed. I don't know if it depends on the severity of the hip dysplasia as to what type of cast or harness can be used, my daughters' was not too bad. She is now 7 months old and out of the harness and the doc says she looks great.
Just something more to think about I guess