How old is the meaning of late marriage and late childbirth in eight-character fortune telling?

In horoscope fortune telling, people usually get married and have children later than ordinary people. Usually life is normal, and people around the age of 25 get married and have children. Taking this as a standard, the period from 30 to 40 years old is the reference time for late marriage and late childbirth. How many years later, it depends on everyone's specific situation.