UnitedHealth is pulling out of “Obamacare” health coverage in Louisiana next year, forcing about 29,000 people to find a new insurance provider under the federal health care law.

The nation’s biggest health insurer notified Louisiana Insurance Department officials last week that in January it will end its participation in most of its public health insurance exchanges created under the Affordable Care Act.

Its participation in public health insurance exchanges will drop to only a handful of states next year after expanding to nearly three dozen for this year. In an earnings call Tuesday with financial analysts, UnitedHealth CEO Stephen Hemsley said the company has been reviewing its health care law-related business on a state-by-state basis and expects to lose more than $1 billion on it for 2015 and 2016.

Under the Affordable Care Act, state-based health insurance exchanges were created, as was a federal health insurance marketplace for states such as Louisiana that didn’t begin exchanges on their own. Coverage targeted the uninsured, often providing sizable subsidies that make the insurance affordable for lower-income people.

In Louisiana, UnitedHealth insures about 13 percent of the more than 214,000 residents enrolled in “Obamacare” for 2016.

Some local health care industry observers don’t expect the company’s departure will have a major impact. State Insurance Commissioner Jim Donelon did not return a call for comment Tuesday.

Brian Burton, state director of the Southwest Louisiana Area Health Education Center, said UnitedHealth’s plans were typically priced in the middle tier. Still, he said, having more insurers competing for business against one another was better for consumers.

“I don’t think it’s going to have a huge impact,” he said, adding, “I think all of this is going to balance itself out if those (other) providers are willing to hang in there.”

As of December, UnitedHealth had 28,944 Louisiana members signed up in the federal marketplace, according to Ileana Ledet, deputy public affairs commissioner at the state Department of Insurance. Rounding out the rest of the marketplace, Humana had 26,380 members; Vantage covered 6,768; and various Blue Cross and Blue Shield of Louisiana plans dwarfed them all at more than 161,000 customers.

The UnitedHealth members in Louisiana will have to sign up with a new insurer during the 2017 open enrollment period, which runs Nov. 1 to Jan. 31.

UnitedHealth’s pullout is not a surprise. In December, the company cut its earnings forecast, and Hemsley told investors that the insurer should have learned more about the still-new business and that expanding before it did that was “for us, a bad decision.”

He said UnitedHealth would have to decide whether to participate in the market for 2017.

Hemsley said Tuesday that the overall market size and “shorter-term, higher-risk profile within this market segment continue to suggest we cannot broadly serve it on an effective and sustained basis.”

Blue Cross and Blue Shield of Louisiana has said the Affordable Care Act expanded access to health insurance to millions of Americans, regardless of age or health status, and doesn’t do enough to encourage healthy people to enroll.

B. Ronnell Nolan, president and chief executive officer of Baton Rouge-based Health Agents for America, said she wasn’t too surprised by UnitedHealth’s news.

A dozen nonprofit health insurance cooperatives that were created by the Affordable Care Act to sell coverage on the exchanges to ensure competition already have folded. That includes one in Louisiana that received more than $66 million in federal funds to get it started.

Those that have survived also have lost millions from higher-than-expected insurance claims, Nolan said.

“It’s kind of like the writing’s been on the wall,” Nolan said. “It seems like every day, there’s a new twist and turn, and the consumer’s the one that’s losing,” Nolan said.

Louisiana’s already high cost of providing health care makes it an obvious candidate for an insurer that’s halting service elsewhere to do the same here, said Walter Lane, an associate professor at the University of New Orleans who studies health care economics.

“Louisiana is one of the most high-cost states,” he said. “We’re also one of the poorer states.”

Overall, UnitedHealth Group Inc. expects to lose $650 million this year on its exchange business, worse than an earlier projection of $525 million. The insurer lost $475 million in 2015.

UnitedHealth, which covers 795,000 people under state exchanges, already had decided to pull out of Arkansas, Georgia and Michigan in 2017, and Hemsley told analysts during Tuesday’s conference call that his company will not carry financial exposure from the exchanges into 2017.

“We continue to remain an advocate for more stable and sustainable approaches to serving this market,” he said.

Analysts expect other insurers to also trim their exchange participation in 2017, especially if they continue to struggle with high costs.

The Associated Press contributed to this report.