Sonia Limas would drag her daughters to the emergency room whenever they felt sick. As an undocumented immigrant, the 44-year-old single mother had no health insurance and the only place she knew to seek treatment is the hospital, also known as the most expensive setting for those covering the cost.

About a decade ago, the family’s options improved somewhat with the expansion of community health clinics, which offered free or low-cost care with help from the federal government. However, President Barack Obama’s health care overhaul threatens to roll back some of those services if clinics and hospitals are overwhelmed with newly insured patients and can’t afford to care for as many poor families.

Obama’s law was never intended to help an estimated 11 million undocumented immigrants like Limas. Instead, it envisions that 32 million uninsured Americans will get access to coverage by 2019. Because that should mean fewer uninsured patients showing up at hospitals, the Obama program slashed the federal reimbursement for uncompensated care.

But in states with large undocumented immigrant populations, the math may not work, especially if lawmakers don’t expand Medicaid, the joint state-federal health program for the poor and disabled.

When the reform has been fully implemented, undocumented immigrants will make up the nation’s second-largest population of uninsured, or about 24 percent.

In communities “where the number of undocumented immigrants is greatest, the strain has reached the breaking point,” wrote Rich Umbdenstock, president of the American Hospital Association, in a letter to Obama, asking him to keep in mind the uncompensated care hospitals gave to that group.

“In response, many hospitals have had to curtail services, delay implementing services, or close beds.”

The federal government has offered to expand Medicaid, but states must decide whether to take the deal. And some hospitals are scrambling to determine whether they will still have enough money to treat the remaining uninsured.

Realistically, taxpayers are already paying for some of the treatment provided to undocumented immigrants because hospitals are required by law to stabilize and treat any patients that arrive in an emergency room, regardless of their ability to pay. The money to cover the costs typically comes from federal, state and local taxes.

A solid accounting of money spent treating undocumented immigrants is elusive because most hospitals do not ask for status. California, which is home to the nation's largest population of undocumented immigrants, spent an estimated $1.2 billion last year through Medicaid to care for 822,500.

Seeking to curb expenses, hospitals might change what qualifies as an emergency or cap the number of uninsured patients they treat. And although it's believed states with the most undocumented immigrants will face a smaller cut, they will still lose money.

Community clinics are a key part of the reform plan and were supposed to take up some of the slack for hospitals. Clinics received $11 billion in new funding over five years so they could expand to help care for a swell of newly insured who might otherwise overwhelm doctors' offices. But in the first year, $600 million was cut from the centers' usual allocation, leaving many to use the money to fill gaps rather than expand.

There is concern that clinics could themselves be inundated with newly insured patients, forcing many immigrants back to emergency rooms.

For now, Limas will return to the emergency room, where the attendants help her fill out paperwork to ensure the government covers the bills she cannot afford.

"They always attended to me," she said, "even though it's slow."

Based on reporting by the Associated Press.

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