Everyone is probably different. I have a few good friends who got pregnant quite young, and it was the best thing for them. Now they are in their early 30's and the kids are growing up so they have a bit more freedom.
DP and I had carefree 20's which we are grateful for. We've done our partying, done our big overseas trips and adventures, gotten to a good point in our careers so i imagine if we do have kids soon, our 30's will be spend doing family stuff. DP is a real family man, and we come from a big family full of kids, so i think we'll just go with the flow. I am grateful though, that we've had our bit of freedom.
Every person is different.