This abortion pill is at the centre of a US legal battle. Here's what you need to know

The US Supreme Court has issued a ruling that pauses the impact of a Texas judge's decision to halt the pill's distribution.

Reproductive rights activists are fighting to keep mifepristone legal in the US. Source: AAP / Olga Fedorova

Key Points

• Mifepristone accounts for more than half of the abortions in the US.
• It's at the centre of the ongoing battle over reproductive rights in the US.
• The Biden administration is seeking to retain women's access to the drug.

The Supreme Court of the United States has weighed in on the legal battle over an abortion pill that accounts for more than half of the abortions in the US, freezing restrictions imposed on the drug by an appeals court.

"As a result of the Supreme Court's stay, mifepristone remains available and approved for safe and effective use while we continue this fight in the courts," Joe Biden said in a statement issued by the White House, following the 21 April Supreme Court decision.

Biden's administration is seeking to retain women's access to mifepristone in the face of abortion bans enacted by Republican-led states since the Supreme Court in June 2022 overturned the landmark 1973 Roe v Wade decision that had legalised the procedure nationwide.

How widespread is abortion pill use in the US?

According to the Guttmacher Institute, the pill accounted for more than half - 53 percent - of the 930,160 abortions documented by the reproductive health research and policy organisation in the United States in 2020.

That was up from 17 percent in 2008 and 39 percent in 2017.

While the number of so-called medication abortions has gone up dramatically in the United States in recent years, it is still not as prevalent as in several European nations.

In France, for example, medication abortions represented 70 percent of the total number of abortions in 2020.

How does it work?

The abortion pill is different from the "morning after" pill, which is taken by a woman after sexual intercourse to prevent becoming pregnant.

The abortion pill is taken to induce an abortion once a woman confirms that she is pregnant.

The process in fact involves more than one pill. The first, mifepristone, also known as RU 486, stops a pregnancy from proceeding normally by blocking production of the hormone progesterone.

Another drug, misoprostol, is taken up to 48 hours later and causes cramps, bleeding and the emptying of the uterus.

Abortion pills can be used at home and a medical setting is not required.

When was the abortion pill approved?

The US Food and Drug Administration (FDA) gave the green light to mifepristone and misoprostol in 2000 for use up to seven weeks of pregnancy.

It was later approved for use up to 10 weeks of pregnancy, after which a woman would need to undergo an abortion through other means, such as vacuum aspiration.

A group opposed to abortions has challenged the FDA's approvals of mifepristone in federal court in Texas.

The average cost of a medication abortion at Planned Parenthood is $580 but it can cost up to $800.

Is it safe and effective?

Use of the abortion pill during the specified time period is considered to be safe and effective by medical experts.

Pregnancies are successfully terminated in more than 95 percent of cases where the pill is used, according to studies.

Serious complications - excessive bleeding, fever, infection or allergic reaction - which require a medical consult, are rare.

The abortion pill does not work for ectopic pregnancies, which account for around two percent of all pregnancies and where a fertilised egg grows outside the uterus.

Where is the pill available?

At least 13 US states have banned most abortions, including medication abortions, since the Supreme Court's ruling in June 2022 overturning the constitutional right to an abortion.

Despite the bans, a number of organisations have mobilised to provide abortion pills to women in states where abortion is restricted.

The extent of their efforts is difficult to evaluate.

In the states where abortion is legal, the FDA recently loosened restrictions surrounding mifepristone, allowing it to be sent through the mail with a prescription or to be sold directly in pharmacies like any other drug.

Can the abortion pill be accessed in Australia?

In Australia, abortions are legal after concerted efforts by campaigners to decriminalise it in each state and territory jurisdiction.

South Australia is the latest jurisdiction to decriminalise abortion, with the changes to come into effect from 7 July.

Since 2012, the mifepristone pill also known as RU486 was added by the Therapetuic Goods Administration to the register for the therapeutic goods, allowing it to be distributed in Australia in accordance with abortion laws.

Access to the pill comes via a prescription by a doctor registered with the TGA's authorised prescriber scheme under strict conditions and ethical oversight. As an alternative to surgery, the pill is used in a two-stage abortion process until nine weeks' gestation.

The mifepristone pill is taken first to end the pregnancy and then 24-48 hours later, misoprostol tablets are consumed.

Access to the pill is patchy and uneven across Australia, particularly in regional and rural parts of the country, due to cost and access issues.