I am doing the dex therpay at the moment, I have a 5 year old son. Myself, my husband and my son have been DNA tested because for pre-natal testing you need to know the exact mutation, there are several for all different CAH types you can carry. I carry a different mutation than my husband for example. I entirely agree with you that this whole area is extremely difficult. On the one hand we have the very important desire that affected females are not virilised and that the developing female brain is not exposed to male hormones whilst on the other we do not really know the effects of dexamethasone on the fetus and in later life and of course we will also expose normal if that is the right word fetuses to dexamethasone. The side effect to mothers are high blood pressure, stretch marks, weight gain, mood swings, I take 20micrograms of Dex per body weight (1300 mcg daily dose) three times a day. I will have the CVS done at 11 weeks although this carries a higher chance of miscarriage (1;75) but as they take genetic material the results are within 24-48 hours, the amnio would be at 15 weeks with 2 weeks for the results as they need to cultivate the cells from the fluid in the lab. However the chance of miscarriage is 1:200. There is no garantie that the dex will work, some girls have still required surgery, however not so extensive as without the dex treatment. However, there have also been some reported side effect on the babies generally, such as failure to thrive and concerns about their ability to handle blood glucose. Even for babies who had the dex until the prenatal testing. I found the decision quite difficult considering all the side effects. You can read up on some of the studies done, especially by Dr Maria New and in Sweden on this website: choose PubMed Medline and then type in congenital adrenal hyperplasia, there are lots of pages, look for prenatal therapy articles and then chose related material, it will give you all the information you need. http://www.ncbi.nlm.nih.gov/