The number of children is not growing any longer in the world. We are still debating peak oil, but we have definitely reached peak child.

Hans Rosling (1948–2017), the Swedish physician and statistician behind Gapminder, repeatedly used the phrase “peak child” in talks and interviews to explain a key demographic turning point: the world’s total number of children has stopped increasing. He linked this to falling fertility rates as countries move through the demographic transition (especially improved child survival, women’s education, and access to contraception). Rosling often contrasted public anxiety about unchecked population growth with data showing that while total population may still rise, the cohort of children has stabilized—implying future growth comes mainly from larger adult cohorts living longer.

Rosling’s point is that global population dynamics have changed in a way many people have not noticed. “Peak child” reframes the debate: instead of imagining endlessly expanding numbers of children, we should recognize that the size of the next generation has leveled off, and that future population growth is largely “momentum” from existing young adults and increased longevity. The comparison to “peak oil” is rhetorical: unlike disputed forecasts about resource peaks, the stabilization of the child population is presented as an observable fact grounded in demographic data. The implication is policy should shift from panic about runaway births to investing in health, education, and planning for aging societies.