What should be the requirement for having children if we had some?

This is open to any option no judegments but people will vote anyway. I've just been curious about the trends of women having children much later in life past their fertile stages, sometimes using IVF and with no partner because they waited too long or put a career first. Times have changes, but nature hasn't and it is interesting how we have to manipulate in order to get what we want when we want.