Editor's note: Kay S. Hymowitz is the William E. Simon Fellow at the Manhattan Institute and writes on childhood, family issues, poverty and cultural change in America. She is the author of "Marriage and Caste in America: Separate and Unequal Families in a Post-Marital Age," "Liberation's Children: Parents and Kids in a Postmodern Age" and "Manning Up: How the Rise of Women Is Turning Men Into Boys."
(CNN) -- "Why is the teen birth rate in the United States so high, and why does it matter?" Those questions are posed in the title of a new paper in the Journal of Economic Perspectives getting a good deal of applause on the Internet.
The answer to the first question, given by authors Melissa Kearney and Phillip Levine, is poverty, or more precisely, inequality. Their answer to the second question -- Does teen pregnancy matter? -- is no.
That's wrong -- or at least misleading -- on both counts.
As Kearney and Levine observe, the United States has the highest teen pregnancy rate in the developed world -- higher than Western Europe, Scandinavia, South Korea and Japan. It also has the highest rates of poverty and inequality.
Almost all our teen mothers are low-income, poorly educated and low-skilled. Ever since teen pregnancy was defined as a major social concern, policymakers have tried to put a brake on the trend on the reasonable presumption that having a child in the teen years limits a girl's -- not to mention her baby's -- chances. The typical proposed solution? More sex education and contraception.
Kearney and Levine poke this story full of some well-deserved holes. Comparing otherwise similar girls who had a baby in their teen years with those who got pregnant but miscarried, they find that teen moms and their childless, or temporarily childless, sisters end up in similarly poor economic straits. Having a baby at 16 doesn't change the "low economic trajectory" of poor girls; they're going to be poor whether they're doing 2 a.m. feedings or not.
According to the authors, poor teens know this. "[I]f girls perceive their chances at long-term economic success to be sufficiently low even if they do 'play by the rules,'" they write, "then early childbearing is more likely to be chosen." Sex education and more access to birth control don't make much difference because, in economist-speak, early childbearing is a rational choice for poor girls.
But to reach this ultimate conclusion you have to ignore the considerable evidence that poor girls who "play by the rules" actually have a pretty good chance of moving out of poverty. According to the Swedish economist Markus Jantii, Americans have the lowest rates of upward mobility of any developed country; a full 42% of men born to a father in the bottom fifth quintile are still there as adults. But for women, Jantii found, the odds are very different. About three-quarters of daughters of low-income men managed to move out of poverty. In fact, when it comes to economic opportunity, American girls are much closer to their counterparts in the egalitarian Nordic countries than they are to American boys.
Scholars who study mobility have learned a bit about who the movers are. Ron Haskins and Isabel Sawhill, both of the Brookings Institute, have calculated that if someone at the bottom does three things -- completes high school, works full time and marries before he or she has children -- the chance of staying poor falls from 12% to 2%, and the chance of joining the middle class or higher rises from 56% to 74%.
So why do so many people assume poverty is a no-exit condition? In Kearney and Levine's case, part of the problem is the no-longer-useful distinction between teen and the broader category of young, single mothers. Although we can't know for sure from reading their paper, it's a good guess that the authors are not comparing unmarried girls who had their children at 15 and girls who miscarried and did not have kids; they're comparing poor teen mothers and their peers who are likely to be single mothers in a few years.
Teen pregnancy has declined dramatically since the early 1990s; today's typical young single mother is in her early 20s. And despite having a few more years under her belt, plenty of research suggests that at 21, an unmarried mother is not much better off than her sister who really is a "teen mother."
Teen pregnancy, then, does not exactly cause poverty, but early single motherhood does limit poor girls' prospects. Have a baby when you are poor, young and single and you're probably going to stay poor. In fact, this is a universal rule. Early single motherhood, whether at 16 or 22, reduces a girl's chances of getting ahead not just in the United States, but everywhere, including Sweden and other countries with generous welfare policies.
Of course, lousy American schools and a paltry market of marriageable men are also serious impediments for mobility, as are the chaos and stress of life in poor neighborhoods. But you know what's even worse? Letting poor girls think they're going to be losers whether they have a baby or not.
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