progesterone
/proh jes"teuh rohn'/, n.
1. Biochem. a hormone, C21H30O2, that prepares the uterus for the fertilized ovum and maintains pregnancy.
2. Pharm. a commercial form of this compound, obtained from the corpus luteum of pregnant sows or synthesized: used in the treatment of dysfunctional uterine bleeding, dysmenorrhea, threatened or recurrent abortion, etc.
[1930-35; b. PROGESTIN and luteosterone ( < G Luteosteron, synonymous with progestin, equiv. to Luteo- LUTEO- (repr. CORPUS LUTEUM) + -steron (see STEROL, -ONE))]

* * *

Steroid hormone secreted by the female reproductive system that functions mainly to regulate the condition of the endometrium (see uterus), preparing it to accept a fertilized egg.

If the egg is not fertilized, the level of progesterone drops, the uterine lining breaks down, and menstruation ensues. If the egg is fertilized (see pregnancy), the placenta produces progesterone, whose effects include preparing the mammary glands for lactation. Many forms of oral contraception use a synthetic progesterone.

* * *

      hormone secreted by the female reproductive system that functions mainly to regulate the condition of the inner lining (endometrium) of the uterus. Progesterone is produced by the ovaries, placenta, and adrenal glands; in the ovaries the site of production is the corpus luteum tissue, which begins to form prior to an egg's release and continues to grow into the empty follicular space once the egg has left the follicle (a capsule of tissue around the egg). The released egg, if it is fertilized by the male sperm cell, becomes implanted in the uterus, and a placenta forms. The placenta then produces progesterone during the period of pregnancy. If the egg is not fertilized, progesterone is secreted by the ovaries until a few days before menstruation, at which time the level of progesterone drops sufficiently to stop the growth of the uterine wall and to cause it to start to break down, and menstruation ensues.

      Progesterone prepares the wall of the uterus so that the lining is able to accept a fertilized egg and so that the egg can be implanted and develop. It also inhibits muscular contractions of the uterus that would probably cause the wall to reject the adhering egg.

      Progesterone is known to have effects on other female organs. In the ovaries (ovary), progesterone and estrogens are thought responsible for the release of an egg during ovulation. It is believed that if the egg is fertilized, these hormones are influential in the prevention of further egg release until the pregnancy has terminated. This dual action ordinarily prevents the release and fertilization of more than one egg at one time, although two or more eggs are occasionally released. Many oral contraceptives are composed of a synthetic chemical similar to progesterone that inhibits egg growth and release in the ovaries and thereby prevents fertilization. In the fallopian tubes progesterone is thought to stop the muscular contractions in the tube once the egg has been transported. During pregnancy, progesterone also stimulates development of the glands in the breasts that are responsible for milk production.

* * *


Universalium. 2010.

Look at other dictionaries:

  • Progesterone — Systematic (IUPAC) name Pregn 4 ene 3,20 dione …   Wikipedia

  • Progesterone — Progestérone Progestérone Formule chimique de la progestérone Général No CAS …   Wikipédia en Français

  • Progestérone — Formule chimique de la progestérone Général No CAS …   Wikipédia en Français

  • progestérone — [ prɔʒɛsterɔn ] n. f. • 1941; de pro , lat. gestare et (horm)one ♦ Biochim. Hormone sécrétée par le corps jaune (après l ovulation et pendant la grossesse), ainsi que par le placenta. ⇒vx lutéine. La progestérone prépare la muqueuse utérine à l… …   Encyclopédie Universelle

  • progesterone — progesterone. См. прогестерон. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • progesterone — /prodʒeste rone/ s.m. [comp. di proge(stina ) e ster(olo ), col suff. one2]. (fisiol.) [ormone sessuale femminile, prodotto soprattutto nell ovaio] ▶◀ luteina …   Enciclopedia Italiana

  • progesterone — female steroid sex hormone which prepares the uterus for child bearing, 1935, from Ger. Progesteron, coined by Corner and Allen, from progestin (1930, from which it was obtained), on notion of substance which favors gestation, from pro (see PRO… …   Etymology dictionary

  • progesterone — ► NOUN Biochemistry ▪ a steroid hormone released by the corpus luteum that stimulates the uterus to prepare for pregnancy …   English terms dictionary

  • progesterone — [prō jes′tər ōn΄] n. [ PRO 1 + GE(STATION) + STER(OL) + ONE] a steroid hormone, C21H30O2, secreted by the corpus luteum or prepared synthetically, active in preparing the uterus for the reception and development of the fertilized ovum and the… …   English World dictionary

  • progesterone —    This is the hormone secreted after ovulation by the corpus luteum. It is a steroid (a cholesterol with a funny hat), enters receptive cells to stimulate their growth, and acts as an anabolic agent. Estrogen should be viewed as the primary coat …   Herbal-medical glossary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”