Classic demographic transition theory assumed that fertility would decline from high levels and stabilize at the replacement level of around 2.1 children per woman. Yet one-half of the global population now lives in a country where period fertility rates have fallen below 2.1 children per woman.

This report aims to review the theoretical and empirical evidence of the determinants of low fertility. 

This document is part of UNFPA’s technical working paper series.

Paper No. 1 in this series is: Policy responses to low fertility: How effective are they?

Paper No. 3 in this series is: Household Structures and Older Persons