Estimating Long-Term Consequences of Teenage Childbearing - an Examination of the Siblings Approach

One of the remedies to selection bias in estimates of the labour market consequences of teenage motherhood has been to estimate within-family effects. A major critique, however, is that heterogeneity within the family might still bias the estimates. Using a large Swedish data set on biological sisters, I revisit the question of the consequences of teenage motherhood. My contribution is that I am able to control for heterogeneity within the family; I use grade-point-averages at age 16, a pre-motherhood characteristic that differs across sisters within the same family. My findings confirm the presumption that within-family heterogeneity can result in biased within-family estimates. Moreover, my results show that when controlling for school performance, the siblings approach and a traditional cross section yield similar coefficients