They’re not. My colleague Steven Camarota looked at that question, using an extensive survey of women who had undergone abortions.  He found that immigrant woman (ages 15–44) overall have nearly identical abortion rates to natives. But there are relatively few immigrants under 25, where the likelihood to get an abortion is highest; comparing only those over age 25 finds that immigrants actually have a somewhat higher abortion rate.

It only gets worse for the native-born children and grandchildren of Latin American immigrants. Their abortion rate is double that of Latin American immigrants, and more than triple the rate of native-born non-Hispanic whites. The abortion rate for the children and grandchildren of immigrants from Asia is more than double that of U.S.-born whites. Given these dramatically higher rates of abortion, it’s likely the abortion rate will increase as immigration changes the demographic makeup of the population.