MYTHBUSTER · 4 MIN READ

Falling fertility isn’t due to a falling desire to have kids

THE MYTH

“Young people today simply don’t want to have as many children.”

The myth

Some read the data as showing that young adults will have fewer children because they want fewer children. Across the developed world, family sizes are shrinking, and some commentators put almost all of that down to changing preferences and rising costs.

The evidence

1. The birthrate has fallen but desire hasn’t. Stated preference for children has changed very little in the developed world since 1980. The number of children people have has dropped and the gap between what people say they want and what they end up with is growing.

2. People are falling short of their own goals. Current fertility rates are below fertility intentions! In the countries surveyed, fertility rates sit on average 0.13 children below fertility intentions. This means that people aren’t even having the children they intend to have, let alone the number they’d ideally want.

3. The obstacles are underestimated. The gap between expected and actual fertility shows people underestimate what stands in the way. Some obstacles are economic, but many are social. Among Americans over 50 without children, the most common major reason given is “it just never happened.” The second is not finding a partner (33%).

4. “Revealed preference” doesn’t work. Economists often argue that we should judge by what people do (their “revealed preference”), not what they say. But this argument doesn’t take the economics of family far enough! Social and legal norms around commitment are weaker than they used to be and this makes it harder for one partner to judge whether the other will be reliable and supportive. An uninformed agent is likely to make mistakes, and, outside of subcultures with stronger norms in favour of commitment, we are all uninformed agents now. This means that it is common for people to delay having children past their preference.

5. Key facts are widely misunderstood. Fewer than 1 in 5 young women realise how much IVF success drops at later ages. IVF pregnancy rates are around 1 in 6 at ages 40–42, and below 1 in 10 at 43–44 (clinics usually advertise the pregnancy rate as their “success” rate). Around 30% of graduates underestimate how much women’s fertility declines after 35. They also wrongly believe a man’s age has no effect on how quickly or whether conception happens.

6. Information changes plans. When young people are informed of the realities of biological risks, they move forward their intended timing of parenthood in two studies.