le·​vo·​nor·​ges·​trel ˌlē-və-nȯr-ˈje-strəl How to pronounce levonorgestrel (audio)
: the levorotatory form of a synthetic progestin C21H28O2 used especially in oral contraceptives

Examples of levonorgestrel in a Sentence

Recent Examples on the Web Studies suggest that levonorgestrel, the active drug, may not work as well in people with obesity, possibly leading to drug failure and pregnancy, said Dr. Alison Edelman, an OB-GYN and researcher at Oregon Health & Science University, who studies contraception and obesity. Jonel Aleccia, Fortune Well, 7 Nov. 2023 The combination of levonorgestrel and a placebo prevented 63% of pregnancies, while the levonorgestrel-piroxicam duo prevented 95% of pregnancies, researchers found. Byerin Prater, Fortune Well, 16 Aug. 2023 Studies have shown that levonorgestrel is less effective in women with a higher BMI, particularly above 26. Byerin Prater, Fortune Well, 16 Aug. 2023 Half were randomly assigned to take a single 40 mg pill of piroxicam with their single levonorgestrel pill, while the other half were given a placebo pill with their contraceptive medication. Alice Park, Time, 16 Aug. 2023 Only levonorgestrel pills – including Plan B – are available over the counter and without a prescription. Itzel Luna, USA TODAY, 22 July 2023 The first is the one everyone thinks of: Plan B, or levonorgestrel, which is also sold under generic names like Take Action and New Day. Women's Health, 20 June 2023 The first generation progestin includes norethindrone and norethisterone; the second generation, levonorgestrel and norgestrel; the third generation, desogestrel, gestodene, and norgestodene; and the fourth generation progestin, drospirenone and dienogest. Joshua Cohen, Forbes, 4 May 2023 Nonetheless, double dosing is only recommended with levonorgestrel. Rose Stokes, refinery29.com, 5 Dec. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'levonorgestrel.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


lev- + norgestrel, a progestin

First Known Use

1977, in the meaning defined above

Time Traveler
The first known use of levonorgestrel was in 1977

Dictionary Entries Near levonorgestrel

Cite this Entry

“Levonorgestrel.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/levonorgestrel. Accessed 19 May. 2024.

Medical Definition


le·​vo·​nor·​ges·​trel ˌlē-və-nȯr-ˈjes-trəl How to pronounce levonorgestrel (audio)
: a synthetic progestin C21H28O2 that is used especially in birth control pills and contraceptive implants and that is the levorotatory form of norgestrel see mirena, plan b, seasonale, seasonique

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