Unexpected comment

Me and my boyfriend were sitting on the couch this morning after I made him breakfast in bed, when out of nowhere he asks me if I want a baby! I said yes I do and he replies with I do too. We have been together for a year now and he has always said he doesn't want kids for at least 5 years and then he says this out of nowhere. I guess what I'm asking is has anyone else's SO said something similar to you or should I take him seriously? I'm a little lost on what to do at this point.