Bethany Birch had pain in her diaphragm on and off for eight months in 2016.

She knew it was triggered by food so she said she tried taking an antacid, which helped a little, but eventually she avoided eating altogether. She estimated she lost 25 pounds in that time.

One night that September, the pain would not go away for hours. It was so severe she went to the emergency room at Indian Path Community Hospital in Kingsport, Tennessee, where she lives. An ultrasound revealed she needed her gallbladder removed right away. She was able to get into surgery quickly because she hadn't eaten in over 12 hours due to her food avoidance.

At the time, Birch was 23 and uninsured. Once she was released from the hospital, however, she lost her housing and spent months without a permanent mailing address while crashing with family.

"It was a pretty rough situation because, at the time, I didn't have a job, I didn't have a driver's license or anything," Birch said.

For fear of bills she couldn't afford, she said she had often avoided seeking care for emergencies, including a broken finger, asthma attacks, and a sprained ankle. She didn't expect her gallbladder surgery — which cured her pain — to be free.

But she said she never received a bill. She got engaged and moved in with her husband after they married at the end of 2017. Then, in 2018, there was a knock on her door, and she was served a lawsuit.

The patient: Bethany Birch — née Bethany Allison — now 30, a stay-at-home mom. She lacked health coverage at the time of her surgery.

Medical services: Emergency gallbladder removal in 2016, plus a previous visit to the emergency room at the same hospital the same year. A bill later obtained for that visit showed she received treatments consistent with an asthma attack, and while Birch said she could not recall that specific visit, she added that she's gone to the ER so many times for asthma attacks she finds it hard to keep track.

Service provider: Indian Path Community Hospital, which in 2018 became part of Ballad Health, a health system in Tennessee and Virginia.

Total bill: $11,749.60 plus interest, for two hospital visits and additional court costs associated with the lawsuit Ballad Health pursued against Birch. According to an affidavit of debt, she owed the hospital $9,986.40 for gallbladder removal surgery and $1,603.70 for the previous visit. The court judgment ultimately tacked on $159.50 in court costs and an interest rate of 7%. As of May 2023, she had accumulated $2,715.97 in interest.

What gives: In October 2018, Birch was served papers at her home in Kingsport informing her that Ballad Health was suing her for $11,590.10 for two unpaid hospital bills from 2016 — including $9,986.40 for her gallbladder removal.

An executive with the health system later said the hospital attempted to contact her for payment and to discuss charity care. But Birch — who had neither a permanent mailing address nor reliable phone service at the time and could not recall whether she provided the hospital with her email address — said she never received their communications.

Under the Affordable Care Act, hospitals must take certain measures to notify patients of an outstanding bill before pursuing "extraordinary collection actions," like filing a lawsuit. But experts said the law does not account for the individual circumstances that can complicate whether a patient receives that bill.

And when interest is added onto a repayment plan, medical debt can balloon even more. Ballad Health sued more than 6,700 patients over medical debt in 2018, according to an analysis by The New York Times.

Birch brought her father along for support when she showed up to her court date that November, but she did not have an attorney representing her.

"I would never be able to afford one," Birch said.

At the courthouse, she said, she met with a representative from Wakefield & Associates — now known simply as Wakefield — the debt collection and revenue firm representing the health system. Birch signed an agreement to pay the full $11,590.10, plus $159.50 in court costs, in monthly installments of $100 beginning in January 2019.

The court tacked on a 7% interest rate, the default interest rate under Tennessee law at the time of the judgment.

Karen Scheibe Eliason, general counsel at Wakefield, declined interview requests despite Birch's offer to give permission for a representative of the company to speak with KFF Health News about her case.

Anthony Keck, an executive vice president at Ballad Health, reviewed Birch's case with KFF Health News after Birch signed a release waiving federal privacy protections. The health system's timeline indicates a screening of Birch found she was single, uninsured and unemployed at the time of the visit.

Given those circumstances, Birch might have qualified for free or reduced-cost care under the hospital's financial assistance policy for low income patients if she had applied.

Information about the financial assistance option was included in the bills the hospital mailed in September, October, and December 2016, Keck said.

But Birch said she never received the bills, likely because they were sent to an address where she no longer lived. She said she filed a change of address form with the post office in 2017 listing her grandmother's house, where she was staying, but that change would have occurred after the hospital said it sent her bills. She didn't initially update her address, she said, because she didn't have a permanent place to live.

Ballad Health's timeline also indicates a financial counselor left a voicemail for Birch soon after she left the hospital, which Birch said she also did not receive, likely because her pay-as-you-go phone plan was not paid at the time.

Keck said Ballad Health has since changed its financial assistance program to screen and help people like Birch who have barriers in life that could prevent them from applying for financial assistance, such as financial, housing, and food insecurity.

"I think if we had had that system in place" when Birch was being treated, Keck said, "this wouldn't have happened."

The hospital where Birch was treated became part of Ballad Health in 2018, when two competing hospital systems in eastern Tennessee merged, creating one of the largest health systems in the country. According to recent public filings, Ballad Health had an operating revenue of $2.3 billion in 2022 and paid its CEO $2.8 million in 2021.

The resolution: Birch was originally sued for $11,590.10. Since her court-ordered payment plan began, Birch had paid $5,270.20 as of May.

But her balance was still $9,299.82 — $6,583.85 on the principal amount, for her hospital debt and court costs, plus $2,715.97 of accrued interest. After more than four years of payments, she had barely made a dent in her debt.

A KFF Health News-NPR investigation showed many hospitals now commonly use aggressive collection tactics, including sending unpaid medical debt to third-party companies that handle collections, like Wakefield, and pursuing lawsuits against patients.

Keck said Ballad Health does not receive the interest payments. "Interest is mandated by the courts and is directed towards legal fees incurred by the agency collecting on the unpaid patient debt," he said.

In February, Birch started receiving assistance from Ashley Beasley, a patient advocate her grandmother knew from church. Beasley agreed to help Birch as a favor and suggested she reach out to NPR and KFF Health News.

Birch and Beasley said they asked Ballad Health twice that month to settle her debt, but representatives told them Birch needed to work with Wakefield, the debt collector. When they called Wakefield, they said they were told Birch had to work with Ballad Health.

In May, on a phone call with Wakefield representative Anna Elrick, Birch and Beasley again asked to settle the debt, offering to pay an additional $500 on top of what Birch had already paid. Elrick said she would take the offer to Ballad Health. Three days later, Elrick called Beasley to say their offer had been accepted, Beasley said. Birch has since paid the $500 and received a letter from Wakefield acknowledging her account has been paid in full.

Birch called her settlement "bittersweet." On one hand, she said, she feels relief.

"But it's bitter because I know I'm not the only person who's fallen prey to this," she said. "I'm not going to forget that there are other people in my situation, too."

The takeaway: The ACA requires hospitals to make "reasonable efforts" to determine if a patient qualifies for financial assistance before taking them to court. Those efforts specifically include notifying a patient about a financial assistance policy and waiting at least 120 days after providing the first billing statement before initiating a legal process, for instance. Ballad Health's timeline of Birch's case indicates the health system followed those steps.

Zack Buck, a University of Tennessee associate professor who specializes in health law, said the ACA standards leave gaps that patients living in unstable circumstances can fall through.

"What does it mean to provide someone with a bill if it's someone who is not easily reachable and does not have a home?" he said. "It's almost as if the regulations don't even ponder that possibility."

Berneta Haynes, a senior attorney with the National Consumer Law Center, said some states have moved to cap or even ban certain interest charges on medical debt. In Arizona, for example, voters approved a 3% cap on medical debt last year. A Maryland law passed in 2021 prohibits hospitals from charging interest payments for patients who qualify for free or reduced-cost care.

But Haynes said policy initiatives should also focus on how to prevent medical debt in the first place.

"Because once it happens, it seems like the situations get more and more complicated and people get left in these gaps," Haynes 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!

Emmarie Huetteman of KFF Health News edited the digital story, and Taunya English of KFF Health News edited the audio story. NPR's Will Stone edited the audio and digital story.