Millions of women in the US will lose the legal right to abortion, after the Supreme Court overturned a 50-year-old ruling that legalised it nationwide.

The court struck down the landmark Roe v Wade decision, weeks after an unprecedented leaked document suggested it favoured doing so.

The judgement will transform abortion rights in America, with individual states now able to ban the procedure.

Half of US states 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.

In total, abortion access is expected to be cut off for about 36 million women of reproductive age, according to research from Planned Parenthood, a healthcare organisation that provides abortions.

The Supreme Court had been considering a case, Dobbs v Jackson Women’s Health Organization, that challenged Mississippi’s ban on abortion after 15 weeks.

But the court ruled in favour of the state by a majority vote of six to three, effectively ending the constitutional right to an abortion.

Democratic governors of several states including California, New Mexico and Michigan have already announced plans to enshrine abortion rights within their constitutions if Roe v Wade is overturned.

The landmark 1973 Roe v Wade case saw the Supreme Court rule by a vote of seven to two that a woman’s right to terminate her pregnancy was protected by the US constitution.

The ruling gave American women an absolute right to an abortion in the first three months (trimester) of pregnancy, but allowed for restrictions in the second trimester and for prohibitions in the third.

But in the decades since, anti-abortion rulings have gradually pared back access in more than a dozen states.