Numa,
Im sorry that you are going through this. I haave not been in your exact boat but we are simular.
I suffered a MC first time preg so with this preg I have not even wanted to have sex at all in fear that something would happen. I have explained this many times to my DH and he is very ver very understanding. I know he looks at porn on the computer and I am fine with that, what I was getting worried about was that he would start to look to other woman for sex. We talked about this in depth and he has assured me that he made his commitment to me and he unserdands why I dont want to have sex at the moment (tho warming up to the idea of late)
My advice is to be as open and honest with each other and always keep the lne of comunication open.
I wish you all the best and hope it all works out ok.

Kate