Association for Public Policy Analysis & Management

State regulations of fertility control methods include parental involvement (PI) laws for minor seeking abortions. These laws require that an abortion provider notify a parent, or parents, of a minor's request for an abortion, or that the parent(s) provide written consent before a procedure can be performed.  Thirty-nine states currently enforce such statutes. Evidence as to the effect of these laws on teen fertility has not reached consensus. One problem is that researchers have used a difference-in-differences design that compares birth rates of teens exposed to the law, for example, those age 17, to the birth rates of teens seemingly unexposed to the law, for example, those age 18. This approach suffers from misclassification bias because researchers use age at time of delivery to define exposure to the law. However, roughly three-fourths of girls that give birth at age 18 were 17 years old at the time of conception and thus are exposed to the PI law.

In this study we use confidential data from national, natality files (i.e., birth certificates) that provide information on a teen’s exact age in weeks at the time of conception. Consequently, we avoid the misclassification bias associated with using age at time of delivery which results in biased estimates. Moreover, the availability of a precise measure of age at conception also allows us to use an alternative research design—a regression discontinuity (RD) approach—which has not been previously used to study the effect of PI laws. The RD compares the fertility of teens just above and just below the age restriction of the PI laws, which provides, arguably, near random variation in exposure to the law that can be used to assess the impact of PI laws on teen fertility. We also use a more standard difference-in-difference approach, which has potentially greater external validity but with more threats to the internal validity.

Another important aspect of our proposed study is that we include all states and we cover the period from 1989 to 2009 during which the number of states with PI laws almost tripled. The increasing geographic coverage of parental involvement laws over time greatly limited the ability of teens to travel out-of-state to avoid compliance. The long period of analysis enables us to assess whether the effect of PI laws on fertility has changed along with the expanded geographic enforcement.

Initial results indicated that minors who are 17 years and 8 months at conception in states with PI laws are more likely to carry to term than minors who are 17 years and at least 10 months at conception.  However, the results are sensitive to the functional form of the running variable (age at conception) and to whether the state passed a PI law in 1990s relative to the decade afterwards. Preliminary conclusions suggest that PI laws are associated with small increases in births or approximately 2 percent.