Niki Tsongas is preparing for life after politics. After becoming the first woman elected to Congress from Massachusetts in a quarter century, she announced plans last year to leave her seat, prompting the election of incoming Congresswoman Lori Trahan, who is now part of the biggest class of Democratic women ever sent to the capitol. WGBH's Morning Edition anchor Joe Mathieu sat down last week with Tsongas in her office in Lowell to talk about her years of service and her role as a pioneer among women in Washington. The following transcript has been edited for clarity.

Niki Tsongas: I feel so fortunate to have had the experience that I've had, but I also know that there is a time for beginnings and a time for endings, and so I knew that that time had come for me in terms of serving in Washington. Lori Trahan will get to Washington and hit the ground running and serve this district very well. So I feel good about that, and especially as I was the first woman in 25 years, I've taken particular pleasure in the fact that we had a great group of candidates in the primary. I was so proud of the diversity and talent of the group as a whole, given the outcome. I do like to see a woman succeed, a woman for the first time in Massachusetts in terms of who we send to Washington, to Congress.

Joe Mathieu: I wanted to ask you about that, because I suspect you couldn't have imagined, when you arrived in Washington, that we would be talking, in a matter of 10 years or so, about this female Democratic insurgency. Women not just winning seats, but flipping many of them in the House.

Tsongas: Well one thing I've often said, and I'm sure you've seen it written as well, is that we can't win if we don't run. And I think historically we just simply did not run. Am I surprised by now that we now have four women members who will be representing Massachusetts in Washington? Not so much, but I'm reassured by the fact that so many women are seeking to run. And once they make that decision the voters are obviously wanting to see them elected.

Mathieu: So what advice would you have for Congresswoman-elect Trahan and or Ayana Pressley, arriving in Washington now?

Tsongas: Well the thing I've always valued about being in Congress is it's an extraordinary opportunity to make a difference in a multitude of ways. So whether it's helping a constituent who's having a problem with the federal government, a veteran who can't access their benefits, or a senior who's having trouble with Social Security or Medicare, an immigrant, often people who need a visa or a passport to travel, that we can be a resource and we have dedicated a good part of what we do here in the district to that. We focus on economic development. Many of the communities I represent are old and post-industrial cities, businesses. We have very diverse businesses, very innovative businesses. There is a multitude of ways in which a member of Congress can be a resource to those businesses as well, and help foster economic growth and job creation.

But then you weigh in on every issue we face as a country. And while some of those issues are very large, I was proud to vote for the Affordable Care Act, which was a monumental piece of legislation that's still a work in progress. But there are other ways. Every time you get a line in a bill that impacts an entire country, or at least certain people within that country. So it's an opportunity never to be squandered.

Mathieu: I know we've heard from Congresswoman-elect Trahan on this. We're waiting to hear from Congresswoman-elect Pressley. Would you also advise incoming members to vote for Nancy Pelosi?

Tsongas: Everybody has to make their own decision around who they feel it's important to support. But she is a remarkable strategist, manages a very diverse caucus, and I don't see anybody out there who could ever serve this country as well as she has. In essence I think this is a family fight. And I think we run the risk of squandering valuable time if we can't resolve it and put it behind us quickly.

Mathieu: You've been a champion for our armed forces, serving on the Armed Forces Committee, leading the effort to fight sexual assault in the military, and also for more modern, gender-specific body armor. You couldn't have done that without crossing the aisle, though. There's something about bipartisanship that's become abstract in Washington.

Tsongas: Well I was fortunate to receive an appointment to the House Armed Services Committee. I sought it out, I grew up in the Air Force family. I lived all over this country, and the world, actually — went to high school in Tokyo, Japan. And I thought it was a committee that needed more diversity. At the time, there weren't that many women on it. And I didn't realize that it has a great bipartisan tradition. So that was No. 1. Number two, I became aware of the issue of sexual assault very early on. I had been in office about a month or so when we had a hearing about what the services were doing to prevent sexual assault. There was a general from every service testifying before us and I was sort of taken aback. I couldn't really — I thought, "It's that big an issue?"

And maybe a month later I was at a Wounded Warrior luncheon. There were several women there and I went over to talk with them about their experiences and asked them. I said, "You know, we just had this hearing on sexual assault in the military. Is it as prevalent as that hearing would suggest?" One of the women was a nurse. She'd been deployed to Iraq and Afghanistan both several times. She said, "Ma'am, I'm more afraid of my own soldiers than I am of the enemy." And to protect herself, she carried a knife in her waistband. She'd never been assaulted, nor was she ever going to be. But from then on I took it seriously. And I was fortunate to find a compatriot in Congressman Mike Turner, a Republican from Ohio. And year after year we've worked together. And because we've been able to work together, we bring both our parties to the table and we've chipped away at the many, many shortcomings of the way in which the services have either worked to prevent this or worked to respond to these incidents when they happen.

Mathieu: Well Congresswoman, when you consider all of these new members being sworn in at the beginning of the year, I wonder if you have plans for Jan. 3rd. Are you gonna be on a beach somewhere?

Tsongas: Not a beach. I'll probably be on Cape Cod, just doing some long-neglected work on a wonderful house that we have down there. But I will watch with real hope as our new colleagues are sworn in. I have great appreciation for all that young blood brings to our institutions. I look forward to seeing seeing the impact of all these great people who've just been elected to Congress.

Congresswoman Niki Tsongas speaking with WGBH News. She tells us she'll be clearing out her Congressional office by the end of this week, and says Yes, it's sinking in. This is WGBH Radio.