Most people assume that you can just introduce a new baby to your family and not think your dog will be affected by this new object soaking up all his owners time. The truth is, your dog knows when you are pregnant. He can sense it. It sounds goofy, but it is true.
When ever you have that baby shower, open up some of the toys, blankets, anything baby related an introduce it to your dog to let him get used to these unusual smells. Any little thing helps. More baby scent the better. When showing your dog baby things, make sure your praise him to show him that it is ok, whatever this stuff is will not hurt him.
When the baby is taken home for the first time, introduce the baby to your dog with precaution. When doing this make sure you make your dog sit and sniff at your terms and not his. Whenever you feel comfortable, put the baby on the ground and make your dog lay next to your child and show affection towards him to show him that this new object is ok. Your dog needs to know that this new baby is the newest pack leader of this family. It is important for you to praise your dog so he can relate, “the baby is good” with positive reinforcement.