In 2002, an estimated 9.5 percent of all births in the United States were to illegal immigrant mothers, according to a new report by the Center for Immigration Studies (CIS).

The study's author, Steven A. Camarota, notes that births to illegal aliens will complicate efforts to enforce a “temporary” worker program:

[A]s U.S. citizens these children have a right to stay permanently, their citizenship can prevent a parent’s deportation, and once adults they can sponsor their parents for green cards. The large number of children born to illegals also shows that a “temporary” worker program is unrealistic. It would result in hundreds of thousands of permanent additions to the U.S. population each year, exactly what such a program is supposed to avoid. Births to illegal aliens remind us that illegals are not simply workers, but rather they are human beings who, like all people, will have children.