Caitlyn Mai woke up one morning in middle school so dizzy she couldn’t stand and deaf in one ear, the result of an infection that affected one of her cranial nerves. Though her balance recovered, the hearing never came back.

Growing up, she learned to cope — but it wasn’t easy. With only one functioning ear, she couldn’t tell where sounds were coming from. She couldn’t follow along with groups of people in conversation — at social gatherings or at work — so she learned to lip-read.

For many years, insurers wouldn’t approve cochlear implants for single-sided deafness due to concerns that it would be hard to train the brain to manage signals from a biological ear and one that hears with the aid of an implant. But research on the detrimental effects of single-sided deafness and improvements in technique changed all that.

So Mai, now 27 and living near Oklahoma City, was thrilled last fall to get a prior authorization letter from her insurer saying she was covered for cochlear implant surgery.

She had successful outpatient surgery to implant the device in December and soon after was eagerly attending therapy to get her brain accustomed to its new capabilities.

“It was amazing. When I’d misplaced my phone and it rang, I could tell where the sound was coming from and find it,” she said.

Then the bill came.

The Patient: Caitlyn Mai, who is insured through her husband’s job by HealthSmart, which is owned by UnitedHealth Group.

Medical Services: Cochlear implant surgery, including the operating room, anesthesia, surgical supplies, and drugs.

Service Provider: SSM Health Bone & Joint Hospital at St. Anthony, an orthopedic hospital in Oklahoma City that is part of SSM Health, a Catholic health system in the central U.S.

Total Bill: $139,362.74 — or, with a “prompt pay discount” if she paid about two months after surgery, $125,426.47.

What Gives: Providers and insurers often have disagreements over how a bill is submitted or coded, and as they work through them (or don’t), the patient is left holding the bag, facing sometimes huge bills.

“I almost had a heart attack when I opened the bill,” Mai said of the first monthly missive, which arrived in late December. She said she was so upset she left work to investigate. Before surgery, “I’d even checked that all hospitals and doctors were in-network and that I’d met my deductible,” she said.

While she was never threatened with having her bill sent to collections, she said she worried about that possibility when the same bills arrived in January, February, and March, with ominous warnings that “your balance is now past due.”

Mai said she first called the hospital billing office but that the representative could tell her only that the claim had been denied and didn’t know why. She called her insurer, and a representative there said the hospital didn’t adequately itemize its charges or include billing codes. She then called the hospital back and relayed exactly what her insurer said must be done to rectify the bill — and the name and number of the insurance employee to fax it to.

When her insurer told her a week or two later it hadn’t received a corrected bill, Mai said, she called the hospital again … and again.

“I said, ‘I’ve done your job for you — now can you please take it from here?'” she said.

Mai said a hospital staffer promised to fax over the corrected, itemized bill in two to three weeks. “How does it take that long to send a fax,” she wondered. She said she asked to speak with a supervisor and was told the person wasn’t available but would call her back. No one did.

After receiving another $139,000 bill in late February, Mai said, she checked back in with her insurer, but a representative said it had not yet received the revised bill.

Finally, she said, she told the hospital to “just send it to me and I’ll send it over.” This time, she forwarded the bill to her insurer herself. But in late March she got another bill demanding the full amount — and offering an $11,000-a-month payment plan.

Mai said she had met her out-of-pocket deductible and, with prior authorization in hand, expected the surgery to be fully covered.

SSM Health did not respond to multiple requests for comment about why it billed Mai.

“It’s outrageous that the patients end up umpiring the decisions,” said Elisabeth Ryden Benjamin, vice president of health initiatives at the Community Service Society of New York, an advocacy organization. “And it’s outrageous that providers are allowed to bill patients while they’re haggling with the insurer.”

Indeed, more and more patients are stuck with such bills as insurers and hospitals spend more and more time arguing in the trenches, data shows. A recent report by Crowe, an accounting firm that works with a large number of hospitals, found that more than 30% of claims submitted to commercial insurers early last year weren’t paid for more than 90 days — striking compared with the lower rates of such delays in Medicare, which were 12% for inpatient claims and 11% for outpatient claims.

The Crowe report found a particular justification for denying claims was cited at 12 times the rate by commercial insurers as by Medicare: that they needed more information before they would process the submission. Such a request allows insurers to sidestep laws in most states that require claims be paid in 30 to 40 days, automatically granting health plans the right to delay payment.

In a separate analysis, the American Hospital Association complained that increases in insurance denials and delays “strain hospital resources” and “inhibit medically necessary care.”

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But perhaps no one is harmed as gravely as the patient, who is barraged with bills and believes they must pay up — particularly when the missives are stamped “past due” and contain offers of prompt-payment discounts or no-interest payment plans. “The stress and anxiety was huge,” Mai said.

Caroline Landree, a spokesperson for UnitedHealth Group, said the insurer could pay Mai’s claims only “after receiving a detailed bill from her provider.”

“We encourage our members to contact the number on their insurance cards for more information on the status of payments,” she added.

The Resolution: Mai estimated she spent at least 12 hours on the phone doing tasks that typically fall to someone working in a hospital billing department: making sure the bill was coded as needed and that the insurer had what it wanted to process the payment.

More than 90 days after her surgery, after Mai had received four terrifyingly huge bills, her insurance finally paid the claim. Mai owed nothing more.

She added: “I’ve never got that call back from a supervisor to this day.”

The Takeaway: It’s not uncommon for an insurer to delay paying a claim until it receives an itemized bill; providers sometimes get creative with billing codes to increase revenue, and studies show that more than half of hospital bills contain errors. But studies also suggest insurers are wont to drag their feet, niggling over coding and charges — and, in doing so, delaying reimbursement and holding on to the cash.

Medical billing experts say it may not seem right for patients to receive bills as this process plays out but that it’s probably legal.

“Laws say ‘hold the patient harmless,'” Benjamin said. “What we didn’t say is, ‘Don’t send them a bill.'” She said it is also unfair that patients may be forced to act as the go-between for providers and insurers who should be talking to each other.

What’s a patient to do? First step: Don’t pay the bill (aside from a copay or coinsurance) for care or services preapproved by insurance. Call the health care provider and explain they should take up their bill with the insurer.

Second, ask the provider to send an itemized bill with all billing codes used, then review it for errors. As the patient, you would know that you never had an MRI, for example. Your insurer wouldn’t.

If submissions to “Bill of the Month” are reflective of trends, many patients these days are finding themselves ping-ponging between representatives for providers and insurers to get bills resolved and paid.

“Bravo for Ms. Mai for having the energy to keep at it and get resolution,” Benjamin said.

Bill of the Month is a crowdsourced investigation by KFF Health News and NPR that dissects and explains medical bills. Do you have an interesting medical bill you want to share with us? Tell us about it!

KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

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