Abortion was made legal across the US after a landmark legal ruling in 1973, often referred to as the Roe v Wade case.
Now the US Supreme Court has overturned that right making abortion instantly illegal in 22 US states.
The ruling ends constitutional right to an abortion for millions of US women.
Individual states are now able to ban the procedure again. Half of the states in the US are expected to introduce new restrictions or bans.
Thirteen have already passed so-called trigger laws that will automatically outlaw abortion following the Supreme Court’s ruling. A number of others are likely to pass new restrictions quickly.
There are nine judges on the Supreme Court, six of whom were appointed by Republican presidents.
Denouncing the Supreme Court ruling, President Joe Biden urged states to enact legislation to allow abortion – and telling women in states where it was banned to travel to those which did not.
Democratic governors of several states including California, New Mexico and Michigan have already announced plans to enshrine abortion rights within their constitutions.
Former Vice-President Mike Pence, a long-standing critic of Roe v Wade, said: “The judgement has “given the American people a new beginning.
“Having been given this second chance for life, we must not rest and must not relent until the sanctity of life is restored to the centre of American law in every state in the land,” he wrote.
On the other side of the divide, Democratic Speaker of the House Nancy Pelosi said that “the Republican-controlled Supreme Court” had achieved that party’s “dark and extreme goal”.
“American women today have less freedom than their mothers,” she wrote. “This cruel ruling is outrageous and heart-wrenching.”