America's biggest health insurer UnitedHealth bails on Obamacare citing big losses

UnitedHealth, the largest health insurer in the United States, is planning a widespread exit of the Obamacare market due to mounting losses from participating in the program.

UnitedHealth's CEO said in an investor call Tuesday morning that the Obamacare market has continued to show high risk.

"Next year we will only remain in a handful of states," CEO Stephen Hemsley said. UnitedHealth lost $425 million last year due to Obamacare.

The insurer, which had plans in 34 states this year according to the Kaiser Family Foundation, had already said it would pull out of Michigan, Georgia and Arkansas next year.

Though United is the most prominent insurer to announce widespread exit from Obamacare, there has been a broader trend of participating insurers struggling to turn a profit in Obamacare's exchanges. The program has suffered from lower-than-expected enrollment, particularly among younger and healthier customers who are necessary to offset the costs of covering older and sicker enrollees. If insurers start to exit, it will mean less competition, which will drive already rising premiums up even further.