mi·​fep·​ris·​tone | \ ˌmi-fə-ˈpri-ˌstōn How to pronounce mifepristone (audio) , mi-ˈfe-pri-ˌstōn \

Definition of mifepristone

: a drug C29H35NO2 taken orally to induce abortion especially early in pregnancy by blocking the body's use of progesterone

called also RU-486

Examples of mifepristone in a Sentence

Recent Examples on the Web The first is mifepristone, also known as the pill RU-486, which starts the process of safely terminating a pregnancy. Anna Borges, SELF, "11 Questions You Probably Have About the Abortion Pill, Answered by Doctors," 11 Nov. 2019 To terminate a pregnancy with medication, women take two pills: mifepristone, which blocks the hormone progesterone and prevents further growth of the embryo, and misoprostol, which causes the uterus to contract and expel the embryo. NBC News, "Abortion rights advocates, doctors take aim at uptick in 'reversal' laws," 4 Oct. 2019 In the United States, mifepristone and misoprostol typically require a prescription, but there are some pharmacy sites that will provide the drugs without one. Jen Christensen, CNN, "The states with the most online requests for abortion medications," 17 Oct. 2019 The service mails women early in their pregnancy two drugs — mifepristone and misoprostol — after a doctor reviews an online form filled out by the women. Erika Edwards, NBC News, "People are going online for abortion pills, especially in states with more restrictions," 17 Oct. 2019 But taken with another medication called misoprostol, mifepristone can end a pregnancy in the first 10 weeks without the need for an in-clinic procedure. Anna North, Vox, "America’s first generic abortion pill, explained," 20 Aug. 2019 Then on March 29, 2016, nearly 12 years after the law was put on hold, the FDA amended its recommendations for mifepristone, making Ohio’s law moot. Laura Hancock, cleveland.com, "Ohio owes Planned Parenthood, others $383,000 for abortion legal fees, court rules," 25 July 2019 Two pills that end a pregnancy of up to 10 weeks, mifepristone and misoprostol, can be administered at home. Claire Cain Miller And, BostonGlobe.com, "Where Roe v. Wade has the biggest effect," 20 July 2019 The two pills used are mifepristone and misoprostol; the first stops the pregnancy's growth, and the second empties the uterus. USA TODAY, "Some US women are taking reproductive matters into their own hands: They're ordering abortion pills by mail," 25 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mifepristone.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mifepristone

1985, in the meaning defined above

History and Etymology for mifepristone

perhaps from International Scientific Vocabulary amino + fe- (alteration of phen-) + pri- (alteration of prop-) + estradiol + -one

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Time Traveler for mifepristone

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The first known use of mifepristone was in 1985

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Last Updated

19 Jan 2020

Cite this Entry

“Mifepristone.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/mifepristone. Accessed 29 January 2020.

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More Definitions for mifepristone


mi·​fep·​ris·​tone | \ ˌmi-fə-ˈpris-ˌtōn How to pronounce mifepristone (audio) , mi-ˈfep-ri-ˌstōn How to pronounce mifepristone (audio) \

Medical Definition of mifepristone

: a drug C29H35NO2 taken orally to induce abortion especially early in pregnancy by blocking the body's use of progesterone

called also RU-486

More from Merriam-Webster on mifepristone

Britannica.com: Encyclopedia article about mifepristone

Comments on mifepristone

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to assert without proof or before proving

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