Political decisions aimed at curbing rapid population growth in India and China, together with a widespread preference for boys for economic reasons, have led to a situation where both countries now have more men than women. Again and again, the preference for sons over daughters caused families to resort to radical measures, ranging from sex-selective abortions to infanticide, the abandonment of girls, and, in China, the sale of girls after birth.

As early as 1990, Indian economist Amartya Sen, who would later win the Nobel Prize in Economics, warned that more than 100 million women were "missing" in the developing world, and especially in India and China, in the ratio to men.

Today, many men in China and India are unable to find wives because decades of gender imbalance have left far fewer women than men. That is one of the factors that has led to a shift in thinking in both countries — both in politics and society. Educational initiatives, policy measures and the work of activists are all helping to drive forward the change. We hear from people who are facilitating a comeback of girls and who believe that the birth of a girl is a blessing rather than a burden.