Baby fever

My husband and I agreed to have 2 or 3 children. Now after the first he only wants one. Makes me so sad. I'm going to wait till baby is 2 to have the talk with him about how I truly feel about having another. It is something very important to me and something we discussed when we got married. I understand that becoming a parent is hard... But when the time comes how should I talk to him about it. How can we come to a compromise if he still doesn't want another? Is there even a compromise? How can I do things to slowly change his mind if possible? I just don't know what to do... I don't think I can change my mind on the subject but I understand his point of view as well...messy subject. Anyone else go through this or have any advice.?