Would you tell him?

I met this wonderful kickass guy at a concert about a month ago. Everything seems to be some kind of Universal sign with him- for example, we both went to that concert alone last minute because our friends ditched us and ended up dancing together all night. We've hung out two or three times a week since we met, and have been talking constantly since then. He's fucking wonderful. A month later, I just found out I'm pregnant. The catch is that he has a trip to Colorado with his best friend planned at the end of the month (he also invited me). Do you think I should tell him now, and risk ruining his trip, wait until the trip is over and then tell him, or should I just not tell him at all?