Delivering the commencement address at Liberty University, Mitt Romney naturally stuck primarily to "family values" and religious themes. He did, however, make one economic observation that intersects with some fascinating new research. "For those who graduate from high school, get a full-time job, and marry before they have their first child," he said, "the probability that they will be poor is 2 percent. But if (all of) those things are absent, 76 percent will be poor."
These are striking numbers, but surprising new evidence indicates that Romney and others have it backward: Having a baby early does not hamper a woman's economic prospects, as he implies. Rather, young women become mothers because their economic outlook is so objectively bleak.
The problem of teen/single/unwed motherhood is one of the relatively few issues liberals and conservatives seem to be able to agree on these days. The right is more likely to pitch the issue in terms of marital status ("single moms") and the left in terms of simple age ("teen moms"). But both sides reach the same basic conclusion. Raising a child without help from a partner is very difficult. Doing it at an early age is going to substantially disrupt one's educational or economic life at a critical moment, with potentially devastating consequences for one's lifetime. Therefore, preventing early nonmarital pregnancies (whether through liberal doses of contraception and sex education, or the conservative prescription of abstinence cheerleading) would seem universally desirable.
But perhaps we're approaching the problem from the wrong direction, according to Melissa Kearney and Phillip Levine in a new paper "Why is the Teen Birth Rate in the United States So High and Why Does It Matter?" published in the spring issue of the Journal of Economic Perspectives.
They conclude that "being on a low economic trajectory in life leads many teenage girls to have children while they are young and unmarried and that poor outcomes seen later in life (relative to teens who do not have children) are simply the continuation of the original low economic trajectory."
In other words, it is a mistake to the leap from the observation that women who gave birth as teenagers are poor to the view that they're poor because they gave birth. Women with better economic opportunities tend to do a good job of avoiding childbirth.
Kearney and Levine used data on miscarriages to isolate the impact of giving birth from background characteristics that may contribute to a decision to give birth. When used this way as a statistical control, the negative consequences of teen childbirth appear to be small and short-lived. Young women who gave birth and young women who miscarried have similarly bleak economic outcomes. Similarly, when you compare teen mothers not to the general population but to their own sisters who aren't teen moms "the differences are quite modest."
The researchers also discovered that very few policies appear to affect teen birth rate, including abortion policies and sex ed. (Although stingier welfare benefits do appear to cut birthrates a bit.) What really causes birthrates to vary are demographics and state-level economic variables. In particular, teen girls whose mothers have little education are much more likely to give birth than girls with better-educated mothers. Even more interesting is the way that economic inequality amplifies nonmarital births to teen moms. In particular, "women with low socioeconomic status have more teen, non-marital births when they live in higher-inequality locations, all else equal."
The measure of inequality used here is not the fabled gap between the 1 percent and the 99 percent, but the gap between the median income and incomes at the 10th percentile. It measures, in other words, the gap between poor people and the local typical household. It may be a proxy for how plausible it would be for a girl from a low-income household to rise into the middle class. The more difficult that rise seems, the more births there are to unmarried teens.
The upshot is that teen motherhood is much more a consequence of intense poverty than its cause. Family life seems to follow real economic opportunities. Where poor people can see that hard work and "playing by the rules" will reward them, they're pretty likely to do just that. Where the system looks stacked against them, they're more likely to abandon mainstream norms. Those who do so by becoming single teen moms end up fairing poorly in life, but those bad outcomes seem to be a result of bleak underlying circumstances rather than poor choices.
Matthew Yglesias is Slate's business and economics correspondent. His first book, "Heads in the Sand," was published in 2008. His second, "The Rent Is Too Damn High," was published in March.
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