The meaning and measurement of unrealised fertility: A comparison of measures among women aged 40–49 in the United States

Unrealised fertility – when people fall short of their childbearing goals – is inconsistently defined and measured, leading to wide variation in estimates of its prevalence and implications for health and well-being. Using a nationally representative sample of U.S. women aged 40–49, this study compares four potential approaches to measurement, finding prevalence estimates that range from 3.5% to 22.4% across indicators. Multivariable logistic regression models reveal that the social and reproductive health correlates of unrealised fertility also vary according to the selected indicator. Improved measures of unrealised fertility are needed to inform our understanding of fertility barriers, including who is most affected, and policies that support people in achieving their childbearing goals.