chorionic gonadotropin

gonadotropin

 [go´nah-do-tro″pin]

any hormone having a stimulating effect on the gonads. Two such hormones are secreted by the anterior pituitary gland: follicle-stimulating hormone and luteinizing hormone, both of which are active, but with differing effects, in the two sexes. Called also gonadotropic hormone.

chorionic gonadotropin (human chorionic gonadotropin (HCG) (hCG))

1. a glycopeptide hormone that is produced by cells of the fetal placenta and maintains the function of the corpus luteum during the first few weeks of pregnancy. It is thought to promote steroidogenesis in the fetoplacental unit and to stimulate fetal testicular secretion of testosterone. It can be detected by immunoassay in the maternal urine within days after fertilization; this provides the basis for the most commonly used pregnancy test.

2. the same principle obtained from the urine of pregnant women, used in treatment of certain cases of cryptorchidism and male hypogonadism, to induce ovulation and pregnancy in certain infertile, anovulatory women, and to increase the numbers of oocytes for patients attempting conception using assisted reproductive technologies such as gamete intrafallopian transfer or in vitro fertilization; administered intramuscularly. See also choriogonadotropin alfa.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

cho·ri·on·ic go·nad·o·tro·pin (CG),

a glycoprotein with a carbohydrate fraction composed of d-galactose and hexosamine, extracted from the urine of pregnant women and produced by the placental trophoblastic cells; its most important role appears to be stimulation, during the first trimester, of ovarian secretion of the estrogen and progesterone required for the integrity of conceptus; it appears to play no significant role in the last two trimesters of pregnancy, as the estrogen and progesterone are then formed by the placenta. CG has luteinizing hormone activity and exerts its actions through luteinizing hormone receptors.

Synonym(s): β-HCG, choriogonadotropin, chorionic gonadotropic hormone, chorionic gonadotrophic hormone, placenta gonadotropin, placentagonadotropin

Farlex Partner Medical Dictionary © Farlex 2012

chorionic gonadotropin

Human chorionic gonadotrophin A hormone secreted by the anterior pituitary gland, which supports pregnancy Components α-hGH 14.5 kD; β-hGH 22.2 kD. See FSH, Gonadotropin, LH.

Chorionic gonadotropin levels–post conception

Weeks IU/L

1 wks 5-50

2 wks 40-1000

3 wks 100-4000

4 wks 800-10,000

5-6 wks 5000-100,000

8 wks 20,000-200,000

9-12 wks 10,000-200,000

2^nd trimester 8,000-50,000

3^rd trimester 6,000-50,000

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

cho·ri·on·ic go·nad·o·tro·pin

(kōr'ē-on'ik gō-nad'ō-trō'pin)

A glycoprotein with a carbohydrate fraction composed of d-galactose and hexosamine, produced by the placental trophoblastic cells; its most important role appears to be stimulation (during the first trimester) of ovarian secretion of the estrogen and progesterone required for the integrity of the conceptus; it appears to play no significant role in the last two trimesters of pregnancy, because the estrogen and progesterone are then formed by the placenta. Testing for the beta fraction of human chorionic gonadotropin is the basis for most serum and urine pregnancy tests.
Synonym(s): anterior pituitarylike hormone, chorionic gonadotropic hormone, chorionic gonadotrophic hormone.

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

cho·ri·on·ic go·nad·o·tro·pin

(kōr'ē-on'ik gō-nad'ō-trō'pin)

Glycoprotein with carbohydrate fraction composed of d-galactose and hexosamine, extracted from the urine of pregnant women.

Medical Dictionary for the Dental Professions © Farlex 2012