Gender wage and employment gaps are negatively correlated across countries. We argue that non-random selection of women into work explains an important part of such correlation and thus of the observed variation in wage gaps. The idea is that, if women who are employed tend to have relatively...

Until the early decades of the 20th century, women spent more than 60% of their prime-age years either pregnant or nursing. Since then, the introduction of infant formula reduced women's comparative advantage in infant care, by providing an effective breast milk substitute. In addition, improved...