pro·​lac·​tin | \ prō-ˈlak-tən How to pronounce prolactin (audio) \

Definition of prolactin

: a protein hormone of the anterior lobe of the pituitary that induces lactation

Examples of prolactin in a Sentence

Recent Examples on the Web This is because the hormones that promote breast milk production (mainly, prolactin) also suppress ovulation. Christina Oehler,, "Can You Get Pregnant While Breastfeeding? Here’s What an Ob-Gyn Says," 19 June 2019 This is because their effect on the neurotransmitter dopamine may have the potential to increase the levels of the hormone prolactin in the body, which can lead to anovulation in some people. Korin Miller, SELF, "What to Know About Getting Pregnant If You Take Antipsychotics," 17 Jan. 2019 The study authors believe vitamin E reduced the effects of the hormone prolactin, which can contribute to cramps, weight gain and breast tenderness. Amy Capetta, Woman's Day, "10 Foods That Fight Off ALL Your PMS Symptoms," 19 June 2015 To get the highest amount of prolactin, science suggests having an orgasm with a partner if possible. Sandee Lamotte, CNN, "10 health benefits of having more sex," 1 Mar. 2018 Estrogen interacts in various ways with prolactin, a hormone that’s necessary for breastmilk production. Korin Miller, SELF, "7 Signs an IUD Is Right for You—and 5 It Isn’t," 18 Jan. 2018 All of that is coordinated by the hormone prolactin, which activates receptors on cells in your breasts, Dr. Spatz explains. Korin Miller, SELF, "Chelsea Peretti Brought Her Breast Pump to the SAG Awards Because You Gotta Do What You Gotta Do," 23 Jan. 2018 And when the baby starts sucking on your breast, that signals the release of prolactin and oxytocin, which increase milk production and deliver it to your breast. Korin Miller, SELF, "Yup, It's Possible to Breastfeed a Baby You Have via Surrogacy or Adoption," 16 Jan. 2018 First, researchers have observed that the hormone prolactin increases during sleep and causes drowsiness in animals. Dr. Manny Alvarez, Fox News, "5 ways sex benefits your health," 19 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'prolactin.' 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 prolactin

1932, in the meaning defined above

History and Etymology for prolactin

pro- entry 2 + lact- + -in entry 1

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The first known use of prolactin was in 1932

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Cite this Entry

“Prolactin.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2020.

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pro·​lac·​tin | \ prō-ˈlak-tən How to pronounce prolactin (audio) \

Medical Definition of prolactin

: a protein hormone of the adenohypophysis of the pituitary gland that induces and maintains lactation in the postpartum mammalian female abbreviation PRL

called also luteotropic hormone, luteotropin, mammotropin

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