My fiance had a vasectomy.

My fiance had a vasectomy years ago in a previous marriage. We have been together 6 years an recently engaged. He has 2 kids already an I Dont have any. I'm in that point in my life where I would love to become a mother. We have talked about it an he say he wants to have more kids. We agreed that he would talk to his doctor about the options for us. But every time he comes back from a regular check up I ask him did u talk to the doctor about the options we had on conceiving a baby an all he ever says is I forgot... Does anyone have any advise? Its greatly appreciated. :)