Gender Roles and Technological Progress

Until the early decades of the 20th century, women spent more than 60% of their prime- age years either pregnant or nursing. Since then, improved medical knowledge and obstetric practices reduced the time cost associated with women's reproductive role. The introduction of infant formula also reduced women's comparative advantage in infant care, by providing an effective breast milk substitute. Our hypothesis is that these developments enabled married women to increase their participation in the labor force, thus providing the incentive to invest in market skills, potentially narrowing gender earnings differentials. We document these changes and develop a quantitative model that aims to capture their impact. Our results suggest that progress in medical technologies related to motherhood was essential to generate the significant rise in the participation of married women between 1920 and 1960, in particular those with children. By enabling women to reconcile work and motherhood, these medical advancements laid the ground for the revolutionary change in women's economic role.