In this chapter, the authors investigate teen pregnancy and birth rates in developed countries. Babies born to teen mothers tend to have worse health and life outcomes than babies born to older mothers. Studies have demonstrated that the young age of the mother is not the source, but instead these disadvantages are caused by the impoverished circumstances these babies tend to be born into. This issue occurs on a clear social gradient, with wealthy teens the least likely to become pregnant, and poor teens the most likely.

According to a UNICEF study, the developed countries with the highest teen birth rates are the US and the UK, which also rank highest on income inequality. Meanwhile, the countries with lower income inequality such as Sweden, Denmark, and Japan rank lowest in teen births. There are some outliers: for example, Switzerland and Italy have much lower teen births than the authors’ theory would predict, while New Zealand’s is higher. The correlation between teen births and financial inequality is also evident in an analysis of individual US states.

The authors claim that teen birth rates are not related to fertility and insist that unequal societies make teens more vulnerable to early pregnancies and births.