Depends on where you live, I suppose. I know a lot about how it was done back as far as my great-greats and sometimes older, because the church records are meticulous and written with a lot of comments, and notes if there's been any kind of delays. And never would a child be registered years after birth.
It definitely depends where you live. My great grandparents wouldn't make the day's trek down the mountain to the city and sleep in the open just to register a child.