PORTLAND, Ore. » Brittany Maynard will not live to see if her advocacy makes a difference.

The 29-year-old woman expects to die next month. If the brain cancer from which she suffers does not kill her in October, she plans to take advantage of Oregon’s Death with Dignity Act and end her own life on the first of November — a few days after her husband’s 43rd birthday.

Her birthday is Nov. 19.

"That would have been my 30th birthday," she said in an interview Wednesday. "As of right now, I don’t know that I’m going to make it to my 30th birthday, and that’s a really difficult thing to process emotionally."

Maynard and her husband, Dan Diaz, uprooted from Northern California and moved north because Oregon allows terminally ill patients to end their lives with lethal medications prescribed by a doctor.

Rather than silently await death in Portland, she has become an advocate for the group Compassion & Choices, which seeks to expand death-with-dignity laws beyond Oregon and a handful of other states.

"It just seemed like something I couldn’t turn my back on ethically," Maynard said.

A nationwide media campaign featuring Maynard’s story began this week, and it has gone viral.

"It helps me to feel invested in something of worth, something that matters," she said. "Part of what is difficult about becoming so sick is that you lose a lot of your autonomy and your sense of purpose."

Oregon in 1997 became the first state to make it legal for a doctor to prescribe a life-ending drug to a terminally ill patient of sound mind who makes the request. The patient must swallow the drug without help; it is illegal for a doctor to administer it.

More than 750 people in Oregon used the law to die as of Dec. 31, 2013. The median age of the deceased is 71. Only six were younger than 34, like Maynard.

The state does not track how many terminally ill people move to Oregon to die. One of the "frequently asked questions" on the state Public Health Division website is: "How long does someone have to be a resident of Oregon to participate in the act?"

There is no minimum residency requirement, but a patient must prove state residency to a doctor. Some examples of documentation include a rental agreement, a voter registration card or a driver’s license.

Maynard said she and her husband were newlyweds actively trying for a family when she learned on New Year’s Day that she had brain cancer. By spring, she was given just six months to live.

She said relatives accepted her choice.

"I think in the beginning my family members wanted a miracle; they wanted a cure for my cancer." she said. "I wanted a cure for my cancer. I still want a cure for my cancer. One does not exist, at least that I’m aware of.

"When we all sat down and looked at the facts, there isn’t a single person that loves me that wishes me more pain and more suffering."

Barbara Coombs Lee, the author of Oregon’s law and the president of Compassion & Choices, said Maynard approached the group in August.

"Our campaign now is to build public awareness, build public support so great that the politicians can no longer deny it," she said.