(Reuters) - In recent months, some conservative-leaning U.S. states have taken action to curb abortion rights, the most recent being Missouri, where the state’s only abortion clinic could close by the end of the week.

But any attempt to restrict or ban abortion will ultimately face a final test at the conservative U.S. Supreme Court. This is how that process will play out:

CONSTITUTIONAL RIGHT TO ABORTION

There is an accelerating effort by some states and anti-abortion activists to get the Supreme Court to reconsider its landmark 1973 ruling in Roe v. Wade, holding that a woman has a constitutional right to abortion.

The high court reaffirmed Roe in a 1992 decision that said abortion restrictions cannot place an “undue burden” on the right and most recently in 2016, when the court threw out a Texas law that would have imposed difficult-to-meet requirements on abortion clinics and doctors.

The retirement last year of Justice Anthony Kennedy, who co-authored the 1992 decision and joined the 2016 one, has given conservatives a new opening to challenge Roe. Kennedy was replaced by President Donald Trump’s conservative appointee Brett Kavanaugh, who has a thin record on abortion. The court has a 5-4 conservative majority.

RECENT COURT ACTION

The Supreme Court sent mixed messages on its approach to abortion on May 28 when it upheld an Indiana measure that requires fetal remains to be buried or cremated, but stayed out of the fight over a second provision that would have barred abortions based on fetal disability or the sex or race of the fetus.

By rejecting Indiana’s attempt to reinstate the partial ban, the court indicated a reluctance to directly tackle the abortion issue, at least for now.

PENDING CASES

There are other cases pending at the high court aimed at weakening Roe v. Wade.

A case from Indiana challenges a law requiring women to undergo an ultrasound examination at least 18 hours before they undergo an abortion. It was struck down by lower courts.

A separate case concerns an Alabama law that would effectively ban abortions after 15 weeks of pregnancy.

The court is also set to act later this year on a bid by Louisiana to revive restrictions on doctors who perform abortions, requiring that they have hospital admitting privileges.

OTHER STATE LAWS

Alabama’s governor on May 15 signed a law that would outlaw nearly all abortions in the state, the strictest such measure in the United States. It has already been challenged in court.

Other conservative states have passed laws that will face legal challenges. Kentucky, Ohio, Mississippi, and Georgia this year passed bills that would ban abortions when a fetal heartbeat is detected after about six weeks. In January, a federal judge struck down a similar Iowa law and Louisiana is poised to pass its own version.

Missouri’s governor on May 24 signed into law a bill that would ban abortion after eight weeks.

A number of states have passed laws that ban a method of abortion used during the second trimester of pregnancy, known as dilation and evacuation.

Graphic: Abortion laws in the United States - here