Thousands of people have marched across cities in the United States, demanding abortion rights ahead of next month’s key midterm elections.

In Washington, DC, a crowd chanted: “We won’t go back,” as they marched.

They carried posters calling for a “feminist tsunami” and urging people to “vote to save women’s rights”.

“I don’t want to have to go back to a different time,” said Emily Bobal, an 18-year-old student.

“It’s kind of ridiculous that we still have to do this in 2022,” she said, adding that she is concerned that the conservative-dominated high court might next target same-sex marriage.

“The majority of us are ready to get out and fight for democracy and fight for people’s bodily autonomy, women and men,” said Kimberly Allen, 70.

With Democrats battling to maintain their narrow control of Congress, the midterm elections could have a decisive impact on the future of such rights, she said.

Several marchers wore green armbands or scarves, a colour symbolising abortion rights.

Others wore blue, the colour of the Democratic Party, and carried huge flags and banners calling for a symbolic “blue wave” of voters to go to the polls on November 8.

A few counterprotesters made their presence known, some of them urging the crowd to “find Jesus Christ”, while others shouted that “abortion is murder”.

Similar rallies took place in cities including New York and Denver, Colorado.

“The #WomensWave is coming for EVERY anti-abortion politician, no matter where they live,” Rachel O’Leary Carmona, executive director of the nonprofit Women’s March organisation, said on Twitter.

She urged people to elect more women as well as male candidates who support abortion rights.

Polls show Democrats only have a slim possibility of maintaining control of the House of Representatives, but their chances are better in the evenly-divided Senate, where Democratic Vice President Kamala Harris is the tie-breaking vote.

While Republicans have been campaigning largely on soaring prices, immigration concerns and urban crime, Democrats led by President Joe Biden want to shift the debate to abortion rights and the defence of American democracy.

The Supreme Court in June ended the decades-long federal protection of abortion rights, leaving it to individual states to set their own rules.

Since then, several Republican-led states have banned or severely curtailed access to the procedure, provoking a series of legal challenges.

In the latest development, an appeals court in the southwestern state of Arizona on Friday blocked, at least for now, a near-total ban on abortions.