Time to get rid of the dog. If he is already showing jealousy he will not like your husband around the baby. He may be best off in a no child home.
I have an aggressive dog too. He isn't towards me but he is to men and babies. I watched my friends baby and he kept charging at her and snapping. My vet said when my baby gets here to give him the first blanket my baby is in so he gets use to her smell. And to get a baby doll to show him you carrying it and loving it. Do not let him play w it. But if my dog shows any signs of aggression to my little girl he's gone. And being the way he is I will have to put him down. Its sad but I'm afraid someone else would miss treat him do to his aggression issues. I'm hoping for the best but the baby will never be left in a room with that dog! Good luck!!
Talk to the vet, rehoming should be a last resort... He might need some obedience training to correct the behavior but vets have tons of advice on introducing baby to dog!
We have a pit who had food aggression & toy aggression at the time when we found out we were pregnant with our first. My husband and I worked with her diligently every day for six months until our first girl arrived to make sure she did not posses those aggressions with the baby. Well, it has been over six years now and that pit has never even growled at our children. She is the most gentle dog I have ever owned, and is our oldest guardian angel. She loves being anywhere near her. I am very proud that six months of hard and dedicated very precise training has turned into years of the most awesome dog ever.
Please give it some thought. Do a lot of research. And you can most likely redirect the dogs behavior within months. It's not easy. And really does require a lot of work. But the rewards can mean a lifetime of amazing memories.