It may depend on your age at marriage and how long you were seeing each other before you married.
I think it's best to wait for a while, to let your marriage "season," before you have children. But if you were together for some years before you married, and if you're, say, already over 30, you might want to start a family right away.
Older parents, I might add, tend to be better parents.
It's up to the couple, no one else.