In her 40 years as a member of parliament, Harriet Harman has seen sweeping changes in the prospects for women in politics.

Harman was seven months pregnant when she first ran for parliament from Camberwell and Peckham. At the time, the House of Commons was dominated by men. According to Melanie Ward, women’s officer of the Peckham Rye branch of the Labour Party, Harman was seeking to join an exclusive club: “To fight for your place and then be elected as a pregnant feminist MP into a House of Commons that was 97% men in 1982 – must have taken incredible guts and grit”.

But Harman did it and went on to become the longest continuous serving female MP in the Commons, the first to earn the informal title of Mother of the House.

She joined a Labour Party that had just 10 women MPs but as she recently noted, “now there are 104 Labour women and across all parties women MPs are a ‘critical mass’.”

After Tony Blair led Labour to a landslide in 1997, Harman became Britain’s first minister for women, and later, the first minister for women and equalities.

Harman has been deputy leader of the Labour Party and acting party leader after Ed Miliband’s 2015 resignation. She has been a longtime campaigner for gender equality in politics as in everything else, and for more female representation in the cabinet and shadow cabinet.

But now, Harman is stepping down as MP for the south London constituency of Camberwell and Peckham. On December 7, she announced that she would not run for re-election. It prompted an outpouring of tributes.

Rob Holley, chair of the Camberwell and Peckham Labour Party praised Harman for her service to the constituency and fight for equality. In a letter to Harman, Holley wrote: “On behalf of local members, i would like to extend our huge appreciation fro your four decades of service to the people of Camberwell and Peckham, and for your dedication to tackling equality.”

Labour leader Keir Starmer tweeted: “Harriet, your commitment to Labour and Camberwell and Peckham for almost 40 years is phenomenal. A champion for women and social justice – you’ve paved the way for future generations.”

Harman supporter Kathleen Thompson wrote on Twitter: “Thank you for your tireless work on behalf of women in politics and for society more generally.”

Harman’s impending departure has focussed attention on her potential successor as MP for Camberwell and Peckham. Southwark News suggested Camberwell Green councillor Dora Dixon-Fyle, who cites Harman as a “great role model”. So will she follow in Harman’s footsteps and run for parliament? Dixon-Fyle has said that Camberwell and Peckham is “a fantastic constituency, but there’s so much to be done and I’d like to think I’ve got the energy.”

Harman’s admirers and constituents seem to be following her long goodbye with keen interest. One said: “Dora Dixon-Fyle would be a great MP and the perfect person to take over from Harriet Harman. She has been my local Councillor for 20 odd years and she goes out of her way to help her constituents. She is genuine, honest and has a great deal of integrity. Furthermore she is local and loves the communities within the borough. Dora will definitely get my vote.”

For now though, it’s thought Harman’s will be big shoes to fill.