Telling my dad I’m pregnant

So this shouldn’t be an issue and I know that but I’m scared to death to tell my dad I’m expecting, I’m going to be 26 next month. It’s my second child, my first was when I was 17 and he actually handled that quite well considering. Anyway it’s been almost 8 years and I’m still so scared I don’t know what the best way to do this is. He’s is the sweetest Christian man I’ve ever known and he’s my adoptive father so I guess I’m just nervous to disappoint him because I’m not married yet. Any advice?