Nattie the reason you need to go back on your diet is because you have 4 abnormal genes and your partner will either be a carrier or will not be. However the chance of passing PKU still remains and as you will be the one carrying the child, remember everything you eat will directly effect your baby. So if your baby has PKU when born, your levels will be a lot lower thus so will be your baby’s levels. If you ate a normal high protein diet, I would suggest that your baby will need intense levels control at birth. I am not a medic professional but I have had it explained and males do not have to go back on purely because eveything they eat is not effecting the baby. nHope this helps and can I suggest you and your partner speak to your G.P as they can test your partners genes to see if he is a carrier of PKU. If he is not then I believe your child will only ever be a carrier. If he is a carrier he will have 2 abnormal genes and two normal genes, thus if he gives two abnormal genes then you will have a pku baby, if he gives two normal genes you will only have a baby who is a carrier. Remember you have 4 abnormal genes so what ever happens the two genes you give will be abnormal. To be PKU you need 4 abnormal genes. I am not a medical professional this is just what a doctor has told me. I am 27 male who has PKU and my girlfriend is having her genes tested for the same thing. I just want to know the chances of passing it on, I think the doctor told me it is 100/1 chance of it been passed. Not sure if it higher for females with PKU though.