This is really fascinating. The NYT Freakonomics bloggers argue that early weaning from the breast is significantly impacting the declining number of females among India’s overall population:
Stanford’s Seema Jayachandran and Princeton’s Ilyana Kuziemko argue that a preference for boys tempts mothers to wean daughters significantly sooner than their sons.
The earlier they wean, the earlier they can again conceive and roll the dice that this time it’ll be a boy.
Meanwhile, the weaned daughters have been deprived of the health benefits breast-milk and nursing may provide and are more vulnerable to illness and death, particularly in the developing world where the study is focused.
The authors conclude that the “breastfeeding factor” accounts for 14 percent of India’s “missing girls.” More boys survive infancy than girls.