There is great hand-wringing in the United States about what is called the “demographic cliff.” Since the sharp drop in the US birth rate starting in 1976, a further decline after the 2007 Great Recession, and another significant drop in the pandemic years, the number of young Americans has declined precipitously. There are any number of theories about why this drop has happened, from a deliberate attempt to reduce the number of humans inhabiting the planet, to women’s options to prevent or stop pregnancies and therefore bear fewer or no children,