I also agree. Men don't really want to know every detail. they aren't connected to the baby like you are. I also have noticed a lot of woman that hyperfocus on being pregnant as well. It seems to me that some women are so into it that it is over the top. Every breath of the day they are thinking about the pregnancy. This isn't healthy. Learning about it and looking at a book or something once or twice a day to see what size your baby is or to look up a symptom is great but if the whole day is baby focused --- bit much. And I think men get sick of it.
good luck
Agree with the above posters.
Most men aren't interested in the details of pregnancy like women are.
Be grateful he is there for you and the baby.
It's pretty normal for guys to not care as much during the pregnancy, just because they don't experience any of the changes that we do. To them, things are still normal, and not really a huge reality yet. It takes the baby actually being here to make them start really having a feeling towards it, because then it's a reality for them also. Don't worry, it gets better with time.
Just try to give him his space, in this area of your relationship. He will eventually come around. I know it might be disappointing, but involvement is something you really can't force. Ironically, there have been stages in my pregnancy when husband has been more excited than I, and I have been more emotionally numb. When you actually have baby and he has to take a more active role, he will start bonding more w baby. You have to let it run its course. Take care.