QUOTE: “This message is for Sandra. I am seventeen years old and have classical PKU. I have done an enormous amount of research on PKU on women in pregnancy. I also educate the young and the pregnant. I have found (through studies and doctors) that it is NOT good at all to be off diet when a woman is pregnant. This can effect the baby mentally (if it has PKU) even when in the womb of the mother. When the baby is born and mother has not been on diet, this can often times, result in mental retardation (if the baby has PKU) when they are born. Now, depending on the severity of how much the mother has been off diet, will be the severity of how much the babies brain will be damaged (if baby has PKU).” Hello, I’d like to reply to what was said in this young lady’s post. I am a 44 yr. old woman and a mother of 4 sons seriously affected by my PKU. I found out the hard way that you absolutely must be on the diet before you conceive. You kept commenting on if the baby has pku. Rarely do babies born to mothers with pku have pku themselves. I had very little info on PKU pregnancies and was assured by my obgyns-in all 4 of my pregnancies-that being off the diet would not affect my babies. 13 yrs later and now I know. My boys are mildly to moderately mentally retarded, had microcephaly (head smaller than normal) at birth, have severe speech disorders, low muscle tone, A.D.H.D., some autistic-like behaviors, etc. This was a direct result from being subjected to toxic levels of phenylalanine in my system while pregnant with them. None of them have PKU, but are carriers. By the way-I’m new here. Howdy to everyone.