Sociology
Fertility Intentions and Variazioni in Realized Parity in Low-Low Fertility Contexts
Quick fact
In countries with total fertility rates below 1.3, surveys repeatedly show that women intend to have about two children, yet their completed family size averages only 1.2 to 1.5—a striking gap of up to 0.5 children per woman.
Why this is interesting
You might have said you want two kids, but the data shows many people end up with fewer. Why do our intentions so often not match reality?
Read the full explanation
Understanding Fertility Intentions and Variazioni in Realized Parity in Low-Low Fertility Contexts
Imagine you're planning a family. You might dream of two children, but life happens: career timing, financial stability, housing, health, partnership—getting pregnant isn't always straightforward. Fertility intentions are the number of children people say they want (or expect). Realized parity is the number they actually have at the end of their childbearing years. The difference is the parity gap. In very low fertility countries like Italy, Spain, Japan, and South Korea, this gap is large: people collectively intend to have around two children, but the average actual number is well below that. This isn't because people change their minds en masse; rather, barriers—economic, social, institutional—prevent them from reaching their goals. The 'variazioni in realized parity' refers to the observable variation in how many children individuals end up having, even when they share similar intentions. Some manage to have two, others have one or none, and the distribution matters for understanding population trends.
A deeper explanation
The mechanism behind the intention-realization gap lies in the interplay between individual preferences and structural constraints. In low-low fertility contexts, people form intentions based on cultural norms (often two children is the ideal) and personal desires. However, realizing those intentions requires adequate resources: stable employment, affordable childcare, housing, and health support. When these are lacking, couples postpone childbearing, reduce the number of children, or forgo it altogether. For women especially, the opportunity cost of childbearing—career interruptions and lost income—is high. The 'variazioni in realized parity' are not random; they follow systematic patterns: women with higher education, in urban areas, or in precarious jobs often end up with fewer children than they intended. This variation matters because it shows that fertility is not simply a matter of individual choice, but is shaped by social structures and public policies. Understanding these variations helps demographers predict future population changes and helps policymakers design interventions that enable people to achieve their desired family size, which is important for both individual well-being and societal sustainability.