Deborah, He might surprise you. Before I got married, I had 3 wolves (yes, wolves...pure blooded. At the time it was legal in my state to have them) and, of course, they came into my marriage with me. My female wolf had always been terrified of children. When she was only 9 weeks old, I took her to my mother's preschool to let the children see a wolf cub. She snarled and backed away from them even though they were all sitting nicely in a circle. I was shocked! I couldn't believe a pup so young could be so afraid of children. From that moment on, she would growl at children and try to get away from them. If she couldn't or they had cornered her, I am pretty sure she would have bitten them. I had to be vigilant in keeping children away from her. I was heartbroken and had many conversations with my husband about what would happen when we had children. Of course, we agreed she would have to go to a home where there were no children if it became neccessary. 2 years into my marriage, I was expecting my oldest daughter...and worrying about Shadow. When my daughter was born and we brought her home, Shadow sniffed her blankets first. Then we let her see my daughter. She was completely different with her from how she had ever been with children! She wasn't nervous or jealous at all. Shadow was protective, patient, loving and sweet. She was like that with all my children. She followed them everywhere, tolerated the innocent abuses that toddlers inflict with grace and was so devoted I was so proud! In fact, I had to isolate her when other children came to play because if the play got rough, Shadow would go after the offending guest to protect my kids. I got long winded here, but I think that your dog, if introduced to the baby without too much fanfare will be okay. Let your dog sniff a blanket that the baby was wrapped in. When he sniffs it, give him a treat, praise him. If you have a bouncy seat, but the baby in it and let him sniff. Praise him and treat him. Don't wait and let his curiosity build. Do it as soon as you bring the baby home. At first, since the baby won't be making any moves towards your dog, your dog shouldn't feel bothered by him/her, and by the time your baby is getting mobile, your dog should be quite comfortable sharing his home with the baby.
Shadow was 4 years old when my daugher was born and she lived a full life, dying of old age in 2002. She was a devoted, loving dog who never once did anything to concern me once my kids were born. My male wolves were always okay with the kids, but Shadow was truly protective of them. For her to go from scared enough of kids to bite them, to a loving protector of them, was amazing.
I wish you a happy transition, and congratulations!