NORFOLK, Neb. Danielle Lammers, a 35-year-old administrative assistant, wife and mother, had a bump on the back of her lower thigh. It had been there for as long as she could remember, but in July of last year it started to hurt while the family was on vacation at a lakeside cabin in Missouri. Her family doctor referred her to a surgeon who could remove it, though she soon learned she was pregnant and had to put off the procedure until she was in her second trimester.

Both the doctor and the surgeon seemed confident the growth was benign. It wasnt. A biopsy showed that Danielle had clear-cell sarcoma, a rare, potentially lethal cancer that typically affects people aged 20 to 40. Suddenly, Danielle needed another, more invasive operation. And she had to get it at an academic medical center in Omaha two hours away, because the doctors closer to her home in Norfolk, a farming and manufacturing city of about 25,000 residents, had never seen it before.

The surgery was a success. Danielle knew she would need regular screenings for several years to make sure the cancer doesnt return, but she was mostly able to turn her thoughts to getting ready for another baby in the house.

Then came the financial shock: about $50,000 in medical bills.

She and her husband, Tracy, had assumed the bills would be not be a problem. They are members of Medi-Share, one of a handful of nonprofit Christian sharing ministries whose popularity has exploded in the last few years. Like the other ministries, Medi-Share, based in Florida, promotes itself as an affordable, spiritually oriented way to pay for health care. The Lammers had joined about a year and a half earlier, after Danielle lost her job at a large firm in a round of layoffs and took a position at a small business that doesnt provide benefits. Tracy, who is 44 and manages a trailer repair shop, also cant get coverage through work.

The Lammers understood they were not buying a traditional insurance product. The company literature made clear the couple was ultimately responsible for their own bills, and that Medi-Share had limits and offered no guarantees of payment. Still, after listening to their friends in Medi-Share talk about their experiences and after speaking with the companys representatives the Lammers came to believe Medi-Share would take care of their expenses just as well as the company plan they had from Danielles old employer.

But Medi-Share doesnt operate in the way that an employer plan would. After reviewing her records, it determined the tumor was actually a pre-existing condition because, Medi-Share explained in a letter, Danielle had mentioned the bump to her family doctor once before, roughly three years earlier. That made it ineligible for treatment under the ministrys guidelines.

The Lammers were dumbfounded. During the conversation when Danielle had mentioned the bump, it was not causing her discomfort, and the doctor had said not to worry about it. I wasnt medicating it, I wasnt treating it, Danielle said in January, when she first told her story to HuffPost. Its not like every bump becomes cancer.

Tracy called Medi-Shares customer service: I just kept saying, How were we supposed to know? How is anybody supposed to know? After a while, he raised his voice enough that Danielle heard him from another part of the house. It is a Christian place, so you feel guilty even getting mouthy with them, Danielle said. But he kinda had to.

Tracy said it would be more accurate to say he had gotten nicely angry although, he allowed, he might have cursed once or twice.

Eventually a manager got on the line and suggested the Lammers take advantage of an option the rejection letter had mentioned: filing a formal appeal using Medi-Shares internal review process. They did, faxing a letter from their family doctor confirming their recollections about the medical history. Two weeks ago, the Lammers learned that Medi-Share was reversing its decision. It had approved payment for a balance that had, by that point, reached nearly $75,000.

Tracy and I are beyond grateful that Medi-Share has taken the time to listen to our side of the story and re-examine our bills and our situation, Danielle said last week, after learning about the decision. The stress of having to figure out how to pay all of these bills out-of-pocket was devastating.

Although Medi-Share said it could not comment on specifics of the Lammers situation because of confidentiality rules, a spokesperson described its internal review procedure as far more personal and generous than many of the standard appeal processes in the healthcare industry.

Still, the fact that payment was even an issue says a lot about the coverage that sharing ministries provide their members. Pre-existing conditions arent supposed to matter anymore, under the Affordable Care Act. But they matter for people who enroll in ministries and other alternatives to traditional insurance. More and more Americans are doing just that.

Why Sharing Ministries Are Suddenly So Popular

Stories like Danielles were relatively common before the 2010 health care law took effect. Insurance companies selling to individuals rather than through employers routinely scoured medical records for signs that new claims were actually the result of pre-existing conditions that beneficiaries had not disclosed.

Sometimes insurers would refuse to pay for claims or even cancel coverage outright, even if there was scant evidence anybody had covered up an illness. Indignation over the practice reinforced calls for reform, and helped make the enactment of Obamacare and its protections for people with serious medical conditions possible.

Today, people who buy coverage through HealthCare.gov, a state-run analogue like Covered California, or directly from insurers no longer have to worry that prospective insurers will treat them differently or deny them coverage because they have diabetes or cancer. They also know the policies they buy will cover a set of 10 essential benefits, including mental health, maternity care, and prescription drugs, paying for pretty much anything that might be associated with a major illness or injury.

These protections are wildly popular and help explain why Republican efforts to repeal the law outright have repeatedly failed . But the new requirements have also made insurance more expensive, as insurers pay claims they might have avoided before. Although the ACA also created federal tax credits to cut the cost of premiums, the credits are smaller for people at higher incomes and cut off altogether for people with incomes above four times the poverty line (roughly $100,000 for a family of four).

That has created demand for cheaper alternatives, especially for people who dont get much or any financial assistance. Christian health ministry plans are filling that demand.

These plans are not insurance and the law does not treat them that way. They are voluntary arrangements for people who agree to certain conditions, such as abiding by Christian faith, or forswearing alcohol and smoking. They generally do not pay for services that violate religious tenets, such as abortion or maternity coverage from pregnancies out of wedlock. They also offer spiritual support, soliciting prayers for the sick from their members.

Participation in sharing plans has increased from less than 200,000 a decade ago to more than 1 million today, according to the trade association that represents them. It is almost certainly financial appeal, rather than spiritual, that is driving this sudden growth. Joining a ministry can cost hundreds or even thousands of dollars a month less than enrolling in a traditional health insurance plan, especially in areas where premiums under the Affordable Care Act have become most expensive.

But the reason the ministries are so much cheaper is they arent subject to many of the ACAs requirements, even though having a membership in one provides an exemption from paying the individual mandate penalty, which remains in force until 2019.

Some ministries have annual or lifetime limits, or set other restrictions on what they will cover for example, leaving out inpatient psychiatric care. Some limit or exclude preventative care, including basic cancer screenings. People who join sharing ministries must generally agree, in advance, to forgo lawsuits and take any disputes to arbitration. Usually that means biblically based mediation and arbitration , which is a sometimes controversial method that relies partly on religious law. A member with a problem cannot appeal to state insurance regulators for help, because sharing ministries fall outside their jurisdiction.

The ministries have many satisfied members, including people who might otherwise not be able to afford coverage. Some find them to be more personal and nurturing than huge, faceless insurance companies. But as the ministries attract a broader group of customers and market themselves more aggressively as an alternative to Obamacare, they are drawing increasing concern from consumer advocates and regulators.

One worry is that because of the pre-existing exclusions and benefits structure, ministries disproportionately attract and retain people in relatively good health, leaving the traditional insurance market with a relatively sicker group of customers. This drives up costs for insurers offering traditional plans, forcing them to jack up premiums.

The other worry is that people joining the ministries do not fully grasp the limits on their coverage, discovering the truth only when they get sick and suddenly face steep medical bills.

How Ministries Became Part Of The Health Care Landscape

As the Lammers case shows, even vigilant consumers can be confused about what Christian sharing ministries actually cover.

Danielle and Tracy have four children, including a pair of twins, and a fifth now on the way. They live in a single-story ranch-style house near the center of Norfolk, just a few blocks down the street from a bank and a Pizza Hut and about two miles from the childhood home of Johnny Carson , the citys most famous former resident.

The Lammers say they attend church, but less often than they would prefer. Work and the kids make it shard to find the time. Our family has Christ in our hearts and in our home, Danielle said. Unfortunately, making it to a weekly service just doesnt work for us right now, but that doesnt mean we dont believe and have God in our lives.

As they sat in their living room on a frigid January evening, they recounted reading through the Medi-Share literature and talking to friends who were already members. Danielle, who has straight, light auburn hair that falls past her shoulders, was just starting her third trimester at that time, and seemed more perplexed than angry over what was happening.