"Our findings indicate that states that legalized abortion prior to the 1973 Roe v Wade Supreme Court ruling experienced a 4% decline in fertility rates relative to other states. Following the Roe decision, fertility rates in these other states fell by a similar magnitude relative to fertility rates in states that had legalized abortion earlier. The relative reductions in births to teens, women more than 35 years of age, non-White women, and unmarried women were considerably larger. In addition, we found that travel between states to obtain an abortion was significant. Estimates obtained from comparisons between early repeal states and distant states (where travel to obtain an abortion as least likely) indicate that abortion legalization reduced births by 11%. These findings imply that a nationwide prohibition of abortion would have a considerably larger impact on births than would a repeal of Roe v Wade in which abortion remained legal in a handful of states."