The Midwestern state is the first to head to the polls on abortion since the Supreme Court ended the national right to the procedure. The ballot is being monitored closely as a test case for abortion across the country.

Voters in the Midwestern state of Kansas head to the polls on Tuesday in the first major ballot on abortion since the US Supreme Court ended the national right to the procedure.

The June ruling from the United States' highest court, which overturned Roe v. Wade, means people, from state to state, can decide on whether to allow their state legislatures to further restrict or even prohibit abortion entirely.

As a result, the referendum in Kansas is being monitored closely as a test case for abortion rights nationwide, with Republican-dominated legislatures across the US hoping to impose outright bans on the procedure.

Currently, the right to abortion is protected in Kansas' constitution, Tuesday's vote asks whether this should be removed and the responsibility on the issue returned to the control of politicians in the state.

California and Kentucky to vote later this year

The states of California and Kentucky are scheduled to vote on the issue in November, at the same time as midterm elections to Congress, in which both Republicans and Democrats hope to mobilize their supporters across the country on the topic of abortion.

As it stands, abortion in Kansas is legal and the procedure can take place up to to 22 weeks. This law is based on the assertion that a fetus can feel pain at that point.

The decision by the Supreme Court to overturn Roe v. Wade leaves open the possibility of outlawing abortion in each US state. This could leave tens of millions of women forced to travel long distances if they want to undergo the procedure, with several southern and midwestern states considering bans.

US President Joe Biden condemned the ruling by the Supreme Court, saying it was a "sad day" for America and labeling the court's conservatives "extreme." But he said the fight to retain the right to abortion was "not over."

Voters in Kansas will also be casting their ballots in a variety of primaries, including for governor. Polls close at 9 p.m. Eastern Time (0100 UTC/GMT).