I think so if like Penny and I, you are not that keen on the idea of kids. It may be selfish, but we're glad we didn't. Things haven't gone particularly well for us financially over the last couple of years and the burden of children would have been disastrous.
So many people feel pressured into having children and yet, it's really not compulsory. Whatever you have been told either by religious people, family, friends--whoever, it's your choice.
Whilst they do continue your genetic line, we already have a problem with overcrowding--despite what you read and if you are in two minds, then do wait or forego it entirely.
There are plenty of others popping them out like rabbits.