Anthem Inc., the stalwart that has stuck with Obamacare longer than most other large health insurers, is shrinking its participation in the program and pulling out of two more states' marketplaces.

Anthem announced its exit from Wisconsin and Indiana on Wednesday, the deadline in many states for U.S. insurers to file their premium rates if they wish to participate in the Affordable Care Act next year. The insurer said it will leave the two individual insurance markets because uncertainty has become too great to continue offering plans.

The retreat is symptomatic of the current state of haziness in the Obamacare exchanges, with companies struggling to come up with plans and propose premiums while the fate of the law itself is uncertain.