Elizabeth Warren, Republicans fundraise off her account of being fired during pregnancy

As details of one of her signature stump anecdotes about being fired from her role as a first-year public school teacher after becoming "visibly pregnant" presents new questions for Sen. Elizabeth Warren, D-Mass., the Democratic front-runner is not only pushing back but fundraising off of the criticism.

Reports in recent days from multiple news organizations including several conservative outlets cited evidence that they suggested challenges her account of how she was "shown the door" from her job as a special education teacher at an elementary school in Riverdale, N.J. in 1971 when she was around six months pregnant. Warren rebutted these claims in a recent interview with CBS News.

Warren's own past remarks, prior to the 2020 campaign cycle, did not include being forced to leave because she was pregnant. Minutes from school board meetings at that time obtained by ABC News reflect that her teaching contract was at first extended for a second scholastic year.

The Republican National Committee seized the moment Tuesday afternoon in an email claiming Warren had been "caught lying," focusing on a 2007 interview where Warren described leaving her position in different terms than she has since her campaign's start.

The Warren campaign later followed with its own blast, using the moment to ask supporters chip in for the fight.

"My story is not unique," Warren's fundraising email said, "And now, right-wing media outlets are dismissing my story -- and in doing so, dismissing many similar stories of other women who have also been affected by pregnancy discrimination ... As our grassroots movement continues to grow, we fully expect to see more of these far-right hit jobs. Our job is to stop them dead in their tracks."

Late Tuesday night, the campaign also posted a four-minute video on her Instagram account of Warren reading other women's stories about pregnancy discrimination and saying her decision to tell the story about losing her teaching job is a way to “fight back” against what she suffered in the early 1970s, a few years before the Pregnancy Discrimination Act passed.

“When I was 22 years old, I had an experience that a lot of women will recognize. I had been promised a job for the next year, all hired, set to go, and then when they realized I was pregnant, the job was given to someone else,” Warren said in her Instagram video.

"Now this was a long time ago, but we know this kind of stuff still happens today, sometimes subtly and frankly sometimes not so subtly. So, I get out, and on the campaign trail, I tell my story. And I've asked other people to tell their stories as well. I think that's a good way to fight back," Warren continued.

Warren has often said her life story has many “twists and turns.”

The resurfaced documents and video that have raised questions about this particular twist -- an origin story which the top-tier 2020 candidate returns to often on the campaign trail -- date back to a 2007 interview.

In the interview, Warren said that after working at Riverdale Elementary School, she “went back to graduate school and took a couple of courses in education and said, 'I don't think this is going to work out for me'."

"I worked in a public school system with the children with disabilities. I did that for a year, and then that summer I didn't have the education courses, so I was on an 'emergency certificate,' it was called," Warren said in the 2007 interview, which was conducted by the University of California at Berkeley. "I went back to graduate school and took a couple of courses in education and said, 'I don't think this is going to work out for me.' I was pregnant with my first baby, so I had a baby and stayed home for a couple of years."

On the trail, Warren has often described her interaction with the principal as one of the moments that changed the course of her career. She has also called teaching her "first love," adding that she might still be teaching today if it weren't for more "twists and turns." A key part of her stump speech, Warren told the story most recently to a crowd in San Diego: “I was visibly pregnant. And the principal did what principals did in those days — wished me luck and hired someone else for the job,” Warren told the crowd on Saturday.

Warren also detailed the interaction in her 2014 book, “A Fighting Chance,” which she wrote two years into her time in the Senate.

“By the end of the school year, I was pretty obviously pregnant. The principal did what I think a lot of principals did back then — wished me luck, didn’t ask me back for the next school year and hired someone else for the job,” Warren wrote in her 2014 book, “A Fighting Chance,” which she wrote two years into her time in the Senate.

According to records of Riverdale school board meetings obtained by ABC News, Warren was hired in August of 1970 as a substitute teacher. The certificate Warren refers to in the 2007 interview was requested for her by the school board a few months after she was hired as a way to allow her to continue teaching without certain graduate courses.

The graduate course she discussed in the 2007 interview was taken at a nearby school in New Jersey, Kean University, in 1972, the university confirmed to ABC News.

In between when Warren was hired and when she later took that course, school board meeting records show that Warren was offered a job for the following year in April of 1971, when she was about four months pregnant.

By June of 1971, however, when Warren was about six months pregnant and more visibly showing, records show an employment status change: Riverdale had “accepted with regret” her resignation.

According to Warren, her contract was renewed to teach before the principal knew that she was pregnant. It was 1971, which was about seven years before the Pregnancy Discrimination Act banned employers from automatically dismissing pregnant women from their jobs nationwide.

"I was pregnant, but nobody knew it. And then a couple of months later when I was six months pregnant and it was pretty obvious, the principal called me in, wished me luck, and said he was going to hire someone else for the job," Warren told CBS News in an interview.

In addressing the apparent nuances over whether she was specifically fired or pushed to resign, Warren told CBS, "When someone calls you in and says, the job that you've been hired for for next year, is no longer yours, we're giving it to someone else. I think that's being 'shown the door.'"

Mary Ziegler, a professor at Florida State University who focuses on the history of women’s reproductive rights, said Warren’s description matched the context of the era, when teaching was “a classic pink collar job to begin with.”

“The assumption was that after women got married, they probably wouldn't continue working and that definitely after they had children, they wouldn't continue working,” she said. “Pregnancy was to a lot of employers an announcement that women were going to become mothers and therefore remove themselves from public life.”

A local news bulletin from 1971 said that Warren was “leaving to raise a family," while another cited that she had “resigned for personal reasons.”

Those descriptions, Ziegler said, were commonplace.

“The idea that you would be a mother and also work was not something that a lot of employers really believed at the time -- and I there's some evidence that that's still true,” Ziegler added.

Warren now often describes the Riverdale principal’s decision as the reason she switched paths and ended up in law school, the start of a career in bankruptcy law that ultimately led to her election to the Senate and her current run for the presidency.