Media Briefings

The Consequences of Teenage Childbearing: New US Estimates

  • Published Date: September 2013

Teenage mothers in the United States face less desirable outcomes in later life than their peers. But the adverse causal effects of teen motherhood are considerably less than previously thought once account is taken of the fact that girls who give birth in their teens tend to come from more disadvantaged backgrounds.

These are the central findings of research by Adam Ashcraft, Iván Fernández-Val and Kevin Lang, published in the September 2013 issue of the Economic Journal. Their study is able to reach these conclusions by using the fact that girls who experience miscarriages are more likely to come from more disadvantaged backgrounds, making it possible to compare girls who would have given birth had they not miscarried with those who did give birth.

It is widely recognised that teenage mothers suffer serious disadvantages as adults. They are less likely to graduate from high school and to attend post-secondary education. Compared with their peers who did not give birth as teenagers, they have more children, they are somewhat less likely to be married and they have lower personal and family incomes.

Politicians often conclude that teen motherhood is a scourge. But girls who give birth as teenagers also tend to come from disadvantaged backgrounds – and this disadvantage may lead to both their poor adult outcomes and their teen motherhood. Girls who feel they have ‘nothing to lose’ may believe that they will be better off if they have their children while they are still very young.

This study shows that after properly correcting for who gives birth as a teen, the estimated causal effects of giving birth are generally adverse but negligible. In the researchers’ main results, they find that:

· There is no difference in the probability of having a high school diploma and only about one-sixth of a year difference in average education. But there is a four or five percentage point difference in the probability of having a GED (US high school tests of ‘general educational development’).

· Similarly, the estimated effects on marriage are modest: a three to four percentage point reduction in the probability of being married with a corresponding increase in the probability of being divorced or separated.

· Teenage mothers are less likely to be working by about five percentage points. On average, they work about four fewer hours per week, compared with an average of 24 hours per week.

· They also earn about $1,200 less if working or about 6% less than the overall average.

· The estimated effect of being a teenage mother on spouse’s earnings (conditional on having a partner) is trivial and the effect on family income is similarly small.

To understand how the researchers determine whether motherhood causes bad outcomes, consider the following thought experiment. Suppose that it were possible to take a sample of pregnant teenagers and randomly assign only some to give birth. These teenagers could then be followed into adulthood. Because, teen motherhood had been assigned randomly, any differences would reflect the causal effect of teen motherhood on the types of teenagers in the sample.

Fortunately, such experiments are not permitted. But nature comes close to conducting the experiment. Spontaneous abortion – or, in nontechnical language, miscarriage – is nearly biologically random. Very young girls and smokers are somewhat more likely to miscarry.

On the other hand, girls from more favoured backgrounds are more likely to be aware that they are pregnant and therefore they are also more likely to report a miscarriage early in pregnancy. But after adjusting for a few such factors, miscarriage can be treated as biologically random.

Other studies have recognised that miscarriage makes it possible to identify the causal effect of teen motherhood, but this is the first to adjust for the effect of induced abortions. Not all teenagers who miscarry would have given birth otherwise. Some would have had abortions while, by definition, girls who gave birth did not. Since pregnant teenagers who have abortions tend to come from more advantaged backgrounds than those who do not, comparing teenagers who miscarry with those who give birth is not comparing apples with apples.

This study uses a statistical technique to purge the pre-empted abortions from the miscarriages so that it is possible to compare girls who would have given birth had they not miscarried with those who gave birth.

ENDS

Notes for editors: ‘The Consequences of Teenage Childbearing: Consistent Estimates When Abortion Makes Miscarriage Non-random’ by Adam Ashcraft, Iván Fernández-Val and Kevin Lang is published in the September 2013 issue of the Economic Journal.

Adam Ashcraft is at the Federal Reserve Bank of New York. Iván Fernández-Val and Kevin Lang are at Boston University.

For further information: contact Kevin Lang on +1-617-353-5694 (email: lang@bu.edu); or Romesh Vaitilingam on +44-7768-661095 (email: romesh@vaitilingam.com; Twitter: @econromesh).