I became a father after my transition through AI and donor sperm. Before my ex decided that transguys aren't really guys at all, we had talked about what to tell our child and when. (We had started this before she became pregnant). Both of us agreed that telling the child that I was not its biological father was ok, but we differed on the transgender thing. Granted, I was going from F to M and you are going from M to F, but some of the thought processes are the same. By the way, you are really blessed to have a wife who is willing to stay with you and work this through.
I don't know what my son knows now, because we divorced just short of his third birthday and since she changed states, the law says that she got to choose if I had any say in any part of the decisions surrounding his upbringing. She did not want me to, so I don't know. Anyway, I think it comes down to deciding what is best for the child. Today's climate is a little different as far as kids with two moms or two dads etc. Part of that depends on the state you live in. If the child is going to be under three by the time you finish your transition, it will not have any memory of you being in a man's body. Long term memory starts after three years. Your choices are telling your child that you have two moms or going into the fact that you were in a man's body but that it was an "accident of birth" and you had it changed. I don't think that a child who is very young would understand the whole transgender thing, and it may be that starting out with having two moms and then explaining further when the child is mentally capable of understanding is a better solution.
I was adopted, and my parents told both myself and my one adopted brother that since before I can remember. It was never strange or made us feel different for that reason. I've had friends who found out later in life and felt betrayed by their parents for not telling them.
As parent's, we make the best decisions we can for our kids at the time and hope we are doing the right thing. Sometimes we win, sometimes we fall flat. You can't look into the future though and each child is different. Discuss with your wife what makes both of you comfortable and what you think your child would deal with best. Its not a decision that has to be made right away. Even after the baby is born, you still have time to decide. The one thing you will have to decide is what to be called. If you can't decide on Mom or Dad, there are always alternate pet names. Some kids call their parent's by their first names. As long as you follow your hearts and keep your child's welfare in mind, you will do fine.
sam1234
