In the health books I read related to sexuality and the TV shows I watched, as you grow older, the hymen may grow thinner or even separate on its own, as Eliza mentioned. But that's not true for everyone, so it's basically a crapshoot. When you said "older", I thought you meant like in your 30's or 40's. I would think in the 20's your hymen would still be pretty intact. But if you're worried about pain, the basic advice I've always heard is, make sure your lover is tender with you, touches you in ways you like (say something if you like certain touches vs. others), is patient, and helps you get aroused. If you're aroused, you're less likely to be uncomfortable. Some people have pain (like me) and some people don't.