The cost of children by Ruth Mace, explain four causes advanced by the researchers to explain the decline in the number of children being born

The article provides three causes of the decline in the number of children being born.

The first cause is the reduction of mortality. If fewer children die at their youngest age, parents naturally don't need to have more babies so that more of them would survive. Also, there isn't an emotional need to "fill the void" after the death of an infant. This is the so-called risk and mortality factor.

The second cause of fertility decline is the so-called economic-and-investment model, which means how wealthy the families are, and how capable they are of distributing resources among their children. For example, owing or not owing farmland was proved to be one of the very important factors in predicting the fertility rates in a society.

The third cause is the cultural transmission, that is, the transmission of the cultural model of small families with fewer children. This transmission happens via education. However, this conclusion is not enough; education is a bridge between the cultural transmission and economic-and-investment model, as it leads to better social and financial status.