How to break the news?

I just found out I am expecting baby #5. My youngest will be 2 in November, and due to exclusive breastfeeding, my cycle didn't return until April of this year. My husband has said how he has wanted to be done, but, I just wasn't sure that our family was complete. Well, fast forward to this past week and I decided to test early. Sure enough, positive. I am so afraid to tell my husband. I've always been so excited to tell him the news but I just can't find the courage with how negative he has been about the thought of another baby... Advice on how to approach the subject would be extremely helpful. Otherwise I'm afraid I will keep this secret until either morning sickness kicks in or I have my first prenatal appointment.