Highmark Inc.'s contract with the dominant Johnstown-area hospital system is set to expire Monday, and those insured by Highmark Blue Shield already have received letters notifying them that their access to the Conemaugh Health System could be in jeopardy.

But even if the two parties can't reach an agreement in the coming days, most Highmark policyholders who use the Conemaugh system wouldn't see any immediate changes to their access or to the rates they pay.

Both Highmark, Pittsburgh's largest health insurer, and Conemaugh say they hope to strike a deal on reimbursement rates between now and June 30, rendering moot the letters that have been sent out.

"We do continue to negotiate with Conemaugh," said Highmark spokesman Aaron Billger.

"We're still hopeful that we'll reach an agreement by Monday," said Conemaugh marketing director Amy Bradley. Highmark and Conemaugh have been in negotiations since March.

The original contract between Conemaugh and Highmark dates to 1996, and has been extended and amended several times since then. Highmark, according to Mr. Billger, has offered several times to again renew the terms of the existing contract, but Conemaugh declined that offer.

That's what led Conemaugh to terminate the current reimbursement arrangement schedule with Highmark, which in turn led to the letters to 70,000 of Highmark's midstate policyholders.

The letters, sent out in May, urged calm:

"There is nothing you need to do now," the letters said. "At this point, you can continue to receive [care from] the Conemaugh Health System hospitals with no change in your benefits."

Even if the contract between the institutions would be terminated, different policies have different expiration dates.

An employer-paid group product, for example, would remain in effect until the policy's renewal date.

Medicare would be unaffected; state programs such as AdultBasic and the Children's Health Insurance Program, known as CHIP, would have access through Highmark at least through the end of 2008.

Also, even if a contract expires, it's possible for some Highmark members to receive care -- but they'd have to do it at Highmark's "out-of-network" prices, since Conemaugh, in effect, would be outside of the Highmark hospital network.

Johnstown-based Conemaugh Health System operates 800 beds across four hospitals, a cancer center, a neurology center and other outpatient facilities.