Developed countries usually have a much lower fertility rate due to greater wealth and their individualistic culture. Mortality rates are low, birth control is easily accessible, and children often can become an economic drain caused by education costs, clothing and feeding. Longer periods of time spent getting higher education often mean young people have children later in life.

In developing countries on the other hand, children are a needed to provide labor in fields and also to care for their parents in old age. Fertility rates are also higher due to the lack of access to contraceptives.