progesterone

noun pro·ges·ter·one \ prō-ˈje-stə-ˌrōn \

|Updated on: 18 Jul 2018

Definition of progesterone

: a female steroid sex hormone C₂₁H₃₀O₂ that is secreted by the corpus luteum to prepare the endometrium for implantation and later by the placenta during pregnancy to prevent rejection of the developing embryo or fetus; also : a synthetic steroid resembling progesterone in action

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Recent Examples of progesterone from the Web

Zookeepers confirmed the pregnancy with a blood test that showed high levels of progesterone.

— Washington Post, "Once known as the awkward rhino, Stormy fathers baby," 6 July 2018
Dietary deficiencies, abnormal sleep schedules, and stress all release cortisol, which in turn reduces progesterone and estrogen, potentially delaying ovulation, says Kecia Gaither, M.D., an ob-gyn].

— suzannah weiss, Glamour, "Can You Really Hack Your Period to Make It More Regular?," 25 Jan. 2018
Younger women with breast cancer most likely have the triple negative type (estrogen, progesterone and HER2-negative cancer), which, for now, is still most effectively treated by chemotherapy.

— elizabeth varnell, Vogue, "Many Women With Breast Cancer Can Now Skip Chemo, According to a New Study," 4 June 2018
During pregnancy, your body has higher-than-usual amounts of the hormones estrogen and progesterone to support the pregnancy, Julie Levitt, M.D., an ob/gyn with The Women’s Group of Northwestern, tells SELF.

— korin miller, SELF, "'Scandal' Star Katie Lowes Says It Took Her Body 3 Months to Adjust After Her Miscarriage," 22 May 2018
Higher levels of the hormone progesterone in the blubber showed that an average of 63.5 percent of those females were pregnant when sampled.

— marissa fessenden, Smithsonian, "Antarctica’s Waters May Soon Harbor a Boom of Baby Humpback Whales," 5 May 2018
This endometrial tissue, like that in the uterus, changes with the monthly cycle of estrogen and progesterone, causing pain and sometimes bleeding.

— lisa sanders, m.d., New York Times, "The Woman Was Fit and Healthy. Why Did Her Lung Mysteriously Collapse?," 28 Mar. 2018
Some patients are prescribed supplemental hormones like progesterone, which are thought to work by stopping the growth of endometrial tissue.

— nina bahadur, Glamour, "Why Do We Know So Little About Endometriosis?," 7 Mar. 2018
Mirena, Kyleena, Liletta, and Skyla—that release levonorgestrel, a type of progesterone, into the uterus every day.

— lori keong, Marie Claire, "If You’re Freaking Out About Getting an IUD, Here’s What to Know About the Insertion Process," 30 Oct. 2017

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