It is unlikely that the trend towards lower fertility will reverse. “Once having one or two children becomes the norm, it stays the norm,” write Darrell Bricker and John Ibbitson in “Empty Planet: The Shock of Global Population Decline”. “Couples no longer see having children as a duty…to their families or their god. Rather, they choose to raise a child as an act of personal fulfilment. And they are quickly fulfilled.”
生育率走低的趋势会得到扭转的可能性很小。”一旦生一两个孩子称为常态，常态就会保持下去。“Darrell Bricker 和John Ibbitson 在《空旷地球：全球人口数量减少的冲击》中写道。“夫妻不在将生育孩子视为对他们家或对他们神的职责。相反，他们选择将抚养孩子作为一种实现自我的举动。而且他们很快就被满足了。”
The big question-mark hangs over women in poor, high-fertility countries. By 2025 only 1% will live in places where the fertility rate is above 5.0; however, a hefty 32% will live in places where it is between 2.1 and 5.0, predicts the UN. Some people argue that having big families is part of the culture of such places and unlikely to change. Many locals would agree, and their religious leaders would add that God wants them to multiply. But a similar “cultural” preference for large families once prevailed almost everywhere and has changed beyond recognition. So there is no reason to assume that it is immutable.
Others assume that the important factor is the availability of contraception. However, using household surveys in Africa, Mr Lutz found that less than a tenth of women who researchers thought might need birth control cited cost or lack of access as reasons for not using it. The main reasons were lack of knowledge, misplaced fear of health risks and opposition to family planning. None of these things can be changed by handing out free condoms. All require a change of mindset. (Or, in some cases, contraception that a woman can use without her husband knowing.)
Several factors correlate strongly with smaller families. One, as mentioned, is income. Another is urbanisation. Probably the most important, however, is educating girls. The more years they spend in school, the fewer babies they have.
This is hard to disentangle from the other two—richer countries tend to be more urban and to educate girls better. And it is theoretically possible that causality could flow the other way—women who get pregnant as teenagers may be forced to drop out of school. But this effect is likely to be small. When researchers look only at the education that girls receive before they become sexually mature, they still find that more years in school means fewer babies later in life. That suggests that learning reduces fertility, not the other way round.
A truckload of academic studies supports this argument. Education reduces fertility by giving women other options. It increases their chances of finding paid work. It reduces their economic dependence on their husbands, making it easier to refuse to have more children even if he wants them. It equips them with the mental tools and self-confidence to question traditional norms, such as having as many children as possible. It makes it more likely that they will understand, and use, contraception. It transforms their ambitions for their own children—and thus the number that they choose to have.