My understanding with CAH kids, is that achieving height potential is a problem. To little hydrocortisone and your child grows too fast, too soon, thus negatively impacting eventual height. Too much hydrocortisone and the child starts exhibiting Cushing's syndrome symptoms (overweight, small stature, round face). Accordingly, the proper amount of hydrocortisone seems to be rather critical. My answer to your question would be: Yes..it's a little difficult to predict the eventual height of a CAH kid. But it's not unreasonable to assume the chiild will be 1 or 2 standard deviations under their projected height given their parents stature.