More than half of the estimated 11.9 million undocumented immigrants living in the United States lack health insurance and many are more likely to live in poverty than those with legal status, according to a new study from the Pew Hispanic Center.

The 52-page report, “Portrait of Undocumented Immigrants in the United States,” was released Tuesday and picks up where a similar survey left off in 2008. While last year’s survey found that the influx of legal immigrants surpassed that of undocumented immigrants for the first time in a decade, this survey reveals that the latter’s growth rate has completely stabilized.

About 75 percent of the undocumented people in the United States are Hispanic. Mexican immigrants hold the majority (59 percent), although other immigrant groups comprise significant numbers: Asians and Central Americans represent 11 percent of undocumented immigrants each; followed by South Americans at 7 percent; people from the Caribbean represent 4 percent; and Middle Easterners compose less than 2 percent.

The study also found that undocumented immigrants are more likely than either U.S.-born residents or legal immigrants to live in a household with a spouse and children. Of those children, 73 percent were born in the United States, making them citizens. They make up 6.8 percent of the nation’s elementary and secondary school students.

Undocumented immigrants generally have it harder than their legal counterparts. According to the survey, the 2007 median household income for undocumented immigrants is about $15,000 less than that of legal immigrants. Unlike legal immigrants, undocumented immigrants do not earn higher wages the longer they live in the country. More than half do not have health insurance, and 45 percent of undocumented children and 25 percent of citizen-children of undocumented parents are uninsured.