This past January, Brittany Maynard received a horrible and terrifying diagnosis. The 29-year-old newlywed was told she had a rare and advanced brain cancer known as a glioblastoma multiforme. The average survival rate with treatment is 14.6 months; Maynard's own oncologist estimated after a follow-up MRI in April that she had six months to live.

(READ: Brittany Maynard and the debate about death that America needs to have.)

So Maynard did something most Americans do not: she made a plan to die. She and her family decided to move from California to Oregon, so she could take advantage of the state's Death with Dignity Law. That law allows physicians to prescribe terminally-ill patients with a lethal dose of sedatives they can use to end their lives.

752 people have used oregon's aid-in-dying law to end their lives since 1997

On Saturday, Maynard reportedly used the Oregon Death with Dignity Law to end her own life. "Today is the day I have chosen to pass away with dignity in the face of my terminal illness, this terrible brain cancer that has taken so much from me ... but would have taken so much more," Maynard posted on Facebook, according to People magazine.

Oregon is one of five states with an aid-in-dying policy, and its law, passed in 1997, is the oldest in the country. It isn't used by many patients, and it works differently from how many imagine assisted suicide to be.

1) Aid-in-dying requires patients to take their own lives

Discussions of end-of-life care often conjure images of a Dr. Kevorkian figure, who administers a lethal dose of medication to a patient. But the aid-in-dying laws currently on the books work differently. Doctors do not administer a lethal injection; the work that Dr. Kevorkian did would be illegal in Oregon.

Existing aid-in-dying laws give doctors the authority to write a prescription for deadly sedatives. These can be prescribed to a terminally-ill patient who is deemed capable (by a health professional) to make decisions about his or her own treatment.

Patients must make their request for a lethal medication in writing and then, 15 days later, make an oral request. Another 15 days must pass before the patient can fill the prescription — and they could decide never to fill it at all.

"If a doctor is allowed to give a patient a lethal injection, the doctor is the last actor," says Alan Meisel, a bioethicist at the University of Pittsburgh who has written extensively on right-to-die laws. "In Oregon and Washington, the patient is the last actor. And that lets them reserve the right not to act at all."

2) Five states have aid-in-dying laws

On October 27, 1997, Oregon became the first state to allow physicians to prescribe lethal medications to terminally-ill patients. Physicians who wrote these prescriptions would not be allowed to administer the deadly drugs, but could prescribe them to a consenting adult with fewer than six months left to live.

Washington followed with the nation's second assisted suicide law in 2008, and Vermont came after in 2013. There are also two states, Montana and New Mexico, where the court system has found a legal right to assisted suicide. Montana's Supreme Court established the right in 2009, while a Second District Court of Appeals ruling this year created it in New Mexico. The latter case involved two doctors who sought to prescribe fatal drugs to a 49-year-old cancer patient in Albuquerque. The Second District judge writing the opinion wrote, "this court cannot envision a right more fundamental...than the right of a competent, terminally ill patient to choose aid in dying."

3) Few patients seek and are granted aid-in-dying

Oregon has the longest standing aid-in-dying law and has published data every year on how the law works. The releases include information on how many people fill prescriptions for lethal medications, and how many patients ultimately ingest those drugs.

Since 1997, Oregon estimates that a total of 752 patients have died with the aid of these lethal prescriptions, including 72 last year. That accounts for about 0.2 percent of all deaths in Oregon last year. To put it another way: for every 10,000 Oregonians who died in 2013, about 22 of them did so with aid-in-dying prescriptions.

One New England Journal of Medicine study has found that Oregon doctors deny the vast majority of requests received for lethal prescriptions, accepting about one in six. Patients who had symptoms of depression, or viewed themselves as a burden, were less likely to receive a requested prescription.

4) One-third of those who seek aid-in-dying don't ultimately use the drugs

This is, perhaps, one of the more surprising things Oregon has learned with its aid-in-dying law: one in three patients who obtain lethal medications don't end up using the prescription. Through 2013, the state has filled 1,173 aid-in-dying prescriptions, but only 752 of those have been used.

It's possible that some of the more recently filled prescriptions will be taken at some point in the near future, and the ratio of those who use the drugs will increase. But there's a clear pattern of some terminally-ill patients filling these prescriptions but never using them.

"A lot of people view this as buying an insurance policy against a terrible death"

"What this tells us is a lot of people view this as buying an insurance policy against a miserable death," Meisel, the University of Pittsburgh bioethicist, says.

This is similar to how Maynard has described her experience. While she had initially said she planned to take the lethal prescription on November 1, Maynard released a video October 30 saying it was possible she would delay, depending on the state of her health.

"If November 2 comes along and I'm still alive, I know that we'll just still be moving forward as a family, out of love for each other, and that the decision will come later," Maynard says. Maynard did end up using the prescription on November 1, according to People.

5) Aid-in-dying patients are more likely to be affluent and well-educated

When Oregon was debating its aid-in-dying law, opponents worried that it doctors might use it to target lower-income patients who would have trouble paying medical bills. It would be less expensive for those people to die than continue receiving treatments that they may never be able to afford.

Oregon has monitored certain characteristics of those who seek aid-in-dying prescriptions, and they find the opposite has happened. It's the more affluent Oregonians, many of whom are likely more informed about their options in battling a terminal illness, who seek out the lethal drugs.

More than half (53.5 percent) have at least a bachelor's degree. Nearly all (96.7 percent) have some form of health insurance.

6) Nearly all aid-in-dying patients are using some form of hospice care

The Oregon data suggests that aid-in-dying is a complement to hospice care, which aims to make patients comfortable in battling terminal illness, rather than a replacement. In 2013, more than 85 percent of those who used the aid-in-dying law were enrolled in hospice care when at the time of death. One poll has found that residents of states with aid-in-dying laws have higher awareness of hospice options than the general public.

7) Physicians help people die in the 45 states that do not have aid-in-dying

Of course, there are terminally-ill patients who want to end their lives outside of Oregon, Washington, and the three other states where aid-in-dying is legal. This means that some doctors, largely oncologists, end up participating in different versions of assisted suicide. One 2000 survey of more than 3,000 oncologists found that more than 10 percent said they had, at some point in their career, assisted with a patient's suicide.

One approach is aiding patients who have stopped eating and drinking with the express intention of ending their lives. This could involve providing palliative care to make patients who are no longer consuming any nutrients or water more comfortable with the pain (mostly from dehydration) that they'll experience. This can be a lengthy process; Meisel estimates for someone young like Maynard, it could take weeks of not eating and drinking to die.

There are also likely cases where doctors use heavy sedation, with drugs like morphine, with the intention of the patient becoming unconscious and ultimately dying. These methods have not been challenged in court and are therefore generally considered legal, although doctors are often hesitant to discuss how frequently it happens.

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