As she was ushered into surgery eight years ago, Paula was confident that doctors at Washington's Howard University Hospital would find the cancer that had been growing in her right breast for months. She was less certain about where she would wake up the next day.

"I felt scared because of the stories in other states ... It was always in the back of my mind that a doctor, or an immigration officer dressed as a doctor, could take me," said Paula, 60, of the fear that she would be exposed as an undocumented immigrant and deported.

Still cancer-free, Paula, who asked to have her last name withheld, waits in the tiny chapel of La Clinica Del Pueblo, a community health clinic in Washington, DC, where she receives routine care.

She and other illegal immigrants worry that their ability to access healthcare at facilities like La Clinica will become even more risky once President Barack Obama's healthcare law takes effect. The reform requires all U.S. citizens and permanent residents to obtain health insurance, either through the government-run Medicaid program for the poor or by purchasing private insurance via state exchanges starting in 2014.

It also bars undocumented immigrants from participating. As more low-income citizens receive insurance, the fear is that many of the estimated 12 million undocumented immigrants will be easier to identify just because they lack coverage.

"It's my 3 a.m. nightmare," said Alicia Wilson, La Clinica's executive director. "While we do not collect information about the immigration status of our patients, the fact that they will be uninsured could be taken as ‘code' for also being undocumented."

Paula is one of thousands of undocumented immigrants who benefit from the DC Health Care Alliance, one of the most generous taxpayer-funded health plans in the country for patients regardless of income or immigration status. Looking out at La Clinica's crowded waiting room, she firmly clasps the card that gives her membership in the program.

"This is the card that opens a lot of doors ... This clinic has protected us and it is helping us to get the help we need regardless of the risks," said Paula, who entered the United States from Mexico on foot nearly 10 years ago.

In recent years, funding for both the clinic and the healthcare alliance has come under fire from conservative groups who oppose using tax dollars to pay for the care of illegal immigrants, as local governments already struggle with budget cuts in a weak economy.

Wilson and other advocates see that opposition gaining momentum once the healthcare law takes effect, particularly in states where anti-immigration sentiment runs high.


The 4 million U.S.-born children of such immigrants are also vulnerable when policies on immigration and healthcare collide.

According to the Urban Institute, nearly 1 in 10 U.S. families with children are of "mixed status," with at least one parent who is undocumented and one child who is a citizen.

These children are likely to be eligible for insurance, including the government-sponsored Children's Health Insurance Program (CHIP). But many remain out of the system because of their parents' dread that the undocumented spouse will be identified and deported, since U.S. immigration authorities, part of the Department of Homeland Security, must verify a child's residency status.

"You've got a community that's caught in the nexus, the crossroads of two different laws," said Jennifer Ng'andu, a lawyer and deputy health policy director at the National Council of La Raza - a national Latino civil rights and advocacy group.

According to Ng'andu, 8 percent of children from families where both parents are U.S. citizens don't have insurance, compared with 25 percent in households where children live with at least one undocumented parent.

Robert Rector, a senior researcher at the conservative Heritage Foundation, said that making it easier for such families will set an unwelcome precedent that the country cannot afford, even if their children were born within its borders.

"These kids are very expensive. They are getting on average $10,000 a year in public education and welfare and other services that their parents are really going to never earn enough to pay for," Rector said. "If you say this child was born in the U.S. and therefore gets to stay and we're not going to do anything about it, you're kind of creating an unlimited open avenue for future illegal immigration."


Elisabeth, 26, an undocumented immigrant from Mexico City, is a single mother with three children, two of them U.S. citizens. Her worry that government authorities might split up her family is present each time she takes them to the doctor.

"I have a fear of hospitals, questions about my status and am always worried that the police will intervene, that my children will be taken away from me," she said. "I live in the fear with every document I fill out, that it all goes to immigration."

Elisabeth, who also asked for her full name to be withheld, said her own health has been compromised as a result. For two years she suffered in silence as a victim of domestic violence, enduring repeated beatings by her then partner and having her ribs broken while pregnant with her youngest child. The couple has since separated.

The healthcare she has received - such as giving birth to her children in the hospital - has been organized by Mary's Center, another community clinic in the Washington area, and through the DC Health Care Alliance.

While immigrants do have legal protections that allow them to receive care from hospitals and other providers without endangering their status, even the slightest chance of exposure can be terrifying. In the first half of 2011, 46,486 who claimed to have at least one U.S. citizen child were deported, U.S. Immigration and Customs reported.


Ezekiel Emmanuel, a senior Obama healthcare advisor, acknowledges the concern that the law may expose immigrants.

"We were all aware of it," he says. "Is that a negative tradeoff for getting universal coverage? Yes ... It's a visible consequence that we couldn't do anything about given the politics of the situation."

As the political debate over healthcare becomes increasingly focused on cutting costs, experts expect more scrutiny on the fate of undocumented immigrants.

"We're in a time of fiscal austerity where you have 8 percent unemployment among predominantly legal citizens and yet you continue to have a system that openly invites illegal immigrants to come and stay," says the Heritage Foundation's Rector. "The first solution to the healthcare costs is to enforce the law (barring employment to illegal immigrants)."

Some health policy experts disagree, saying U.S. citizens would benefit even more if the health law included undocumented immigrants within its requirements.

Even when immigrants have insurance, their health costs amount to only half or two-thirds of the expenditures seen with U.S.-born citizens, according to a 2009 study by Leighton Ku, director of the Center for Health Policy Research at George Washington University.

"Many people think immigrants are overusing and overtaking emergency rooms, yet all the data shows they use emergency rooms less than citizens. They use everything less than citizens," he said.

Broadening the pool of insured people to include those who use less health care means a larger population can help shoulder the costs of sicker Americans. State health insurance exchanges, which will allow individuals to buy subsidized health plans starting in 2014, exclude illegal immigrants, leaving out millions of young, healthy people who could otherwise spread the risk.

Health insurers are seeking a way around the problem, according to a senior official at one of the largest U.S. insurance companies.

"Here you've got a law which says everybody has to have coverage, but you have classes of people without access to coverage," the official told Reuters on condition of anonymity. "Washington makes it very difficult for us to do the right thing.

"Obviously, we're capitalistic and we want to make money, but at the same time we want the health system to work better, and the health system works better when people have access to coverage."

An estimated 600,000 undocumented workers have private insurance plans through employer-sponsored programs. But they may lose out if their employers can't manage those same plans within the state health insurance exchanges, or if premiums rise. The Restaurant Opportunities Center of Los Angeles, which provides affordable health coverage to 75,000 undocumented restaurant workers, is trying to figure that out.

"It's not merely that they are not eligible for the subsidies, but that they cannot even get a policy from the health insurance exchanges even if they wanted to pay the full cost themselves," Ku said. "If you're an undocumented alien, we still let you go to the store and buy cereal or go to a car dealer and buy a car."