Even some women I know feel the same way as your husband. One of my girlfriends (who now has 4 kids) found her own pregnancy mildly disgusting, and said frequently, "It's just so unnatural," and commented that the baby was a "parasite." When I was pregnant with my first child, I once grabbed the hand of my best girlfriend and put it on my tummy so she could feel. The baby kicked, and my friend jerked her hand away, saying, "Ooooh, gross! It's like 'Alien!' " Some people, no matter how excited they are about the baby find the thought of a living being inside someone's body to be disturbing. Just find ways to share excitement together, instead of wishing he felt differently.
Quite a few family members and friends never got excited for us when I was pregnant. (We have 4 kids.) During the pregnancies, all they wanted to talk to us about was what could go wrong, how expensive raising kids was, how we were too young and too poor, how we didn't need more... you get the picture. After the babies were born, and they were someone sweet to hold and cuddle, and they started being "my niece" or "my grandchild" instead of "your baby," THEN they got excited and adored the child. For some people, it's not "real" until the baby is born. That doesn't mean they don't love you or won't love the baby.
Congratulations! Enjoy your family and this happy time.