The conservative-dominated court overturned the landmark 1973 "Roe v Wade" decision that enshrined a woman's right to abortion, and said individual states can permit or restrict the procedure themselves.
The US Supreme Court has overturned Roe v Wade in a seismic ruling that shreds half a century of constitutional protections on one of the most divisive and bitterly fought issues in American political life.
The court overturned on Friday the landmark 1973 decision that enshrined a woman's right to an abortion and said individual states can permit or restrict the procedure themselves.
The decision, unthinkable just a few years ago, was the culmination of decades of efforts by abortion opponents, made possible by an emboldened right side of the court that has been fortified by three appointees of former President Donald Trump.
The ruling came more than a month after the stunning leak of a draft opinion by Justice Samuel Alito indicating the court was prepared to take this momentous step.
It puts the court at odds with a majority of Americans who favoured preserving Roe, according to opinion polls.
Alito, in the final opinion issued on Friday, wrote that Roe and Planned Parenthood v. Casey, the 1992 decision that reaffirmed the right to abortion, were wrong the day they were decided and must be overturned.
Authority to regulate abortion rests with the political branches, not the courts, Alito wrote.
Joining Alito were Justices Clarence Thomas, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett. The latter three justices are Trump appointees. Thomas first voted to overrule Roe 30 years ago.
Chief Justice John Roberts would have stopped short of ending the abortion right, noting that he would have upheld the Mississippi law at the heart of the case, a ban on abortion after 15 weeks, and said no more.
Justices Stephen Breyer, Sonia Sotomayor and Elena Kagan — the diminished liberal wing of the court — were in dissent.
Thirteen states, mainly in the South and Midwest, already have laws on the books that ban abortion in the event Roe is overturned. Another half-dozen states have near-total bans or prohibitions after six weeks of pregnancy, before many women know they are pregnant.
In roughly a half-dozen other states, the fight will be over dormant abortion bans that were enacted before Roe was decided in 1973 or new proposals to sharply limit when abortions can be performed, according to the Guttmacher Institute, a research group that supports abortion rights.
More than 90 percent of abortions take place in the first 13 weeks of pregnancy, and more than half are now done with pills, not surgery, according to data compiled by Guttmacher.