WASHINGTON (CBS DC) — Physicians are expressing concern that a 90-day grace period rule for health plans covered under the Affordable Care Act will allow insurance companies to deny payment to doctors.

The American Medical Association issued a statement to physicians on Wednesday cautioning doctors on how to navigate a 90-day grace period for government-subsidized health plans. A patient with subsidized insurance who is falling behind in payments is guaranteed coverage for medical bills for 30 days – but insurers can ultimately deny payment during the remaining 60 days.

Some doctors and the AMA say insurance companies could delay and then retroactively deny claims made during the 60-day period – a bill then held stuck with physicians.

“This puts the physician and their patients in a very difficult situation,” Dr. Ardis Dee Hoven, AMA president, told NPR. “If a patient is being treated for a serious illness that requires ongoing care, the physician is having to assume the financial risk for this. That’s the bottom line.”

The AMA and other physician groups are calling on the Obama administration to detail the effect the grace period would have on guaranteed patient care and potentially unpaid physician services.

“The grace period rule imposes a risk for uncompensated care on physicians so the AMA has created resources to help medical practices navigate the key aspects of the rule to minimize its potential negative impact,” Hoven said in a statement. “Managing risk is typically a role for insurers, but the grace period rule transfers two-thirds of that risk from the insurers to physicians and health care providers. The AMA is helping physicians take proactive steps to minimize these risks.”

But earlier this month, the Washington state Legislature passed a prompt-notification law that many consumer advocate groups worry may create strong incentives for doctors to deny treatment up-front.

“The reason they want that notification is so they can start denying services,” Brian Haile, senior vice president for health care policy at Jackson Hewitt Tax Service, told NPR. If the insurer notifies the physician that a patient is behind on premiums and the insurer is holding up claims payments, “Nine times out of 10 the doctor is not going to provide the services — no matter what their network contract says.”

“The doctors aren’t bad guys — they’re business people,” Haile added. “Any economically rational actor would do it.”

One of the larger concerns from physicians noted is that specialty treatment and practices often purchase items prior to treatment – if a patient’s claims are not eventually paid, the high-cost will be left with the doctor.