JOHN YANG: Medicaid is the nation's biggest health insurance program, covering nearly 80 million people.

That's more than one in five Americans.

For many people who have low incomes, are disabled, or who are either very young or very old, it's a vital government program in America's safety net.

MARROW WOODS: So I felt like that will work.

But white chocolate-covered strawberries sounds amazing.

JOHN YANG: Like most college students, Marrow Woods takes full advantage of mom's cooking while home from school.

But on top of keeping up with classes and friends, Woods, who uses they-them pronouns, also balances their health.

MARROW WOODS: There are definitely concerns about my ability to, like, hold a job if I don't have the proper accommodations, or just kind of figuring out a life as a 21-year-old with a chronic illness.

JOHN YANG: Woods has a rare inflammatory skin condition called hidradenitis suppurativa.

It causes painful cysts on their body.

They take experimental medications and go to an Atlanta hospital every month for infusions of a drug to reduce inflammation.

Can you imagine doing this without Medicaid?

MARROW WOODS: Absolutely not.

That has been the one thing, like, getting me through this entire process.

Without Medicaid, I wouldn't be able to receive this medication.

JOAN ALKER, Executive Director, Center for Children and Families, Georgetown University: Medicaid is often the unsung hero of our public coverage system.

JOHN YANG: Joan Alker is the Executive Director of Georgetown University's Center for Children and Families.

JOAN ALKER: Not many people are aware that all poor children in this country have a right to Medicaid.

Medicaid is also the primary payer for long-term care, and it's a key backbone of health care for low-wage workers.

NO NAME GIVEN: The Harry S. Truman Library at Independence, Missouri, is a scene of an historic event.

JOHN YANG: Medicaid was one of President Lyndon Johnson's Great Society programs.

He signed the bill creating it in 1965, offering states federal funds for providing basic health care services to families on public assistance and people with disabilities.

It's voluntary, but by 1982, all 50 states and the District of Columbia had adopted it.

Since then, both Democratic and Republican presidents have signed coverage expansions.

By the late 1980s, the program covered all poor children and all low-income pregnant people.

JOAN ALKER: On many, many of the basics, for example, access to prime and preventive care, Medicaid is performing about as well as private insurance.

There are differences.

Dental care is very hard to access, particularly if you're on Medicaid.

Behavioral health care is another area where it's harder to access, but the answer is not to not give people Medicaid, because then they're in worse shape.

BARACK OBAMA, former U.S. President: This is going to take a little while.

JOHN YANG: In 2010, President Barack Obama's Affordable Care Act expanded Medicaid even further, offering states a generous subsidy if they covered all poor adults.

BARACK OBAMA: We are done.

JOHN YANG: Today, more than 21 million adults have Medicaid because of the ACA.

JOAN ALKER: The marketplaces were kind of the new shiny toy, but Medicaid was kind of the workhorse.

Because the Medicaid expansion for poor adults was really the way in which more uninsured people accessed coverage.

We see Congress turn to Medicaid time and time again because it's a system that's been in place, it works.

Most recently, Congress adopted a new option to allow states to cover postpartum women and people for 12 months after birth.

DR. KEILA BROWN, Chief OB-GYN, Family Health Centers of Georgia: Pain?

NO NAME GIVEN: Sometimes.

JOHN YANG: Dr. Keila Brown is Chief OB-GYN at the Family Health Centers of Georgia.

Many of her patients either are on Medicaid or pay on an income-based sliding scale.

DR. KEILA BROWN: Pregnancy can be very trying on a patient, whether it's emotionally or physically.

And there are a lot of medical issues that can arise during pregnancy or that may have even existed before pregnancy that need continual treatment.

JOHN YANG: Georgia is one of at least 47 states that expanded Medicaid to cover women for a full year after giving birth.

Before, Georgia covered only six weeks.

DR. KEILA BROWN: That finite period was just not sufficient in order to be able to treat any of those things that may have come about during pregnancy or even to put them in a better place post-pregnancy, whether it be for any cardiovascular issues, diabetic issues, which primarily affect the population that we serve.

There's also some mental health issues that go along with being postpartum.

So how are we doing today?

JARICA WILLIAMS: I'm OK.

I'm in postpartum.

It's been a little different this time around.

JOHN YANG: Jarica Williams gave birth to her son, Bryce, two months ago.

Bryce is also covered by Georgia's Medicaid program.

JARICA WILLIAMS: I really appreciate Medicaid.

It takes a large burden off of me, takes some weight off my shoulders when it comes to making sure that my child is getting proper health care.

JOHN YANG: During the pandemic, the federal government increased Medicaid funding to states and prohibited them from kicking recipients out of the program, even if they were no longer eligible.

But when the COVID-19 public health emergency ended last May, states resumed checking eligibility, a process known as unwinding.

So far, 11 million people have lost Medicaid coverage, including more than 4.5 million children.

Some were no longer eligible, but others were dropped for bureaucratic reasons, like re-enrollment forms sent to an old address.

JOAN ALKER: There are many, many ways that Medicaid is working, really to essentially prop up our private health insurance system for people who don't have enough money to be able to afford private coverage, or for people who are disabled, for whom the services that you typically get in an employer-sponsored package simply don't meet their needs.

In our health care system, having coverage is the price of admission.

And you're just not going to see a good show in our health care system if you're uninsured.

JOHN YANG: College student Marrow Woods will soon have to have their eligibility checked.

They can't bear to think about the possibility they may lose coverage.

MARROW WOODS: It's definitely terrifying.

I go to the hospital a lot.

I am in and out of appointments constantly.

And so, without it, there's a lot up in the air about what I could even do, what medications I could have, if I could still afford my medications, so definitely a very stressful time.

JOHN YANG: Tomorrow, we continue our series America's Safety Net with a look at Georgia's unique and controversial program that expands Medicaid coverage, but only to those who meet a work requirement.