It's becoming more and more common for couples to wait until they're later in life to have children. There are many reasons for this, including men and women wanting the freedom to explore and travel in their twenties, not feeling psychologically ready to be parents, wanting to establish themselves and their careers before bringing children into the world, having trouble finding a spouse or having trouble conceiving.
While there are some pros to waiting to have children until you're older, there are some cons as well. For one thing, older parents tend to have less energy than younger parents. They may have a hard time keeping up with their children and being as active as their kids need them to be.
Older parents have a lot to worry about. Will they live to see their children grow up, move out, get married and have children of their own? Will they ever get to meet their grandchildren? As they age, will they become a burden to their kids at a time when their kids are just learning to stand on their own two feet?
When parents are 40 years older than their children, there is a large gap between the values the parents grew up with and the values that are relevant to today's kids. The age difference may become even more of an issue when the children grow to be teenagers, which is a difficult time even for young parents to relate to their kids.
When deciding when in life you want to have kids, you'll have to consider the issue from all angles. It's not a decision to be taken lightly, so make sure you weigh all the pros and cons before deciding whether you want to start a family now or wait until later in life.