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hyperpigmentation in circumscribed areas of the skin; called also melasma.
chloasma gravida´rum melasma gravidarum.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(klō-az'mă), Avoid the misspelling/mispronunciation chlorasma.
Melanoderma or melasma characterized by the occurrence of extensive brown patches of irregular shape and size on the skin of the face and elsewhere; the pigmented facial patches if confluent are also called the mask of pregnancy, and are associated most commonly with pregnancy and use of oral contraceptives.
See also: melasma.
[G. chloazō, to become green]
Farlex Partner Medical Dictionary © Farlex 2012


n. pl. chloas·mata (-mə-tə)
A patchy brown or dark brown skin discoloration that usually occurs on a woman's face and may result from hormonal changes, as in pregnancy.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


An acquired hypermelanosis with “blotchy” coalescent hyperpigmented macules occuring in sun-exposed areas, especially of the face and neck, which is typically seen in pregnancy or with OC use; it is caused by oxidation of tyrosine to melanin and usually regresses with delivery. A similar mask may appear in men without abnormal hormone levels, and in patients treated with phenytoin.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


Melasma, cloasma hepaticum Dermatology A term for melasma-like facial hyperpigmentation, which may be a skin manifestation of pregnancy or chronic liver disease
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Melanoderma or melasma characterized by brown patches of irregular shape and size on the face and elsewhere; if confluent, facial patches are called the mask of pregnancy and are associated most commonly with pregnancy and use of oral contraceptives.
[G. chloazō, to become green]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(klo-az'ma) [Gr. chloazein, to be green]
Tan to brown, sharply defined patches of skin pigment, usually found symmetrically on the forehead, temples, cheeks, or upper lip. The excess pigmentation often occurs in pregnant women, in women using oral contraceptives, or in patients with underlying liver disease. Women are affected more often than men. Sun exposure tends to worsen the condition. Synonym: melasma
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chloasma gravidarum

Brownish pigmentation of the face, often occurring in pregnancy. It usually disappears after delivery. It is also seen in some women who take progestational oral contraceptives.
Synonym: mask of pregnancy See: illustrationillustration

chloasma hepaticum

Liver spot.

idiopathic chloasma

Chloasma caused by external agents such as sun, heat, mechanical means, and x-rays.

chloasma traumaticum

Skin discoloration following trauma.
Medical Dictionary, © 2009 Farlex and Partners


A mask-like area of dark coloration (pigmentation) of the skin around the eyes, nose, cheeks and forehead, which often affects women during pregnancy or when taking oral contraceptives. Chloasma is made worse by exposure to sunlight. The pigmentation usually fades in time.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


A skin discoloration common during pregnancy, also known as the "mask of pregnancy" or melasma, in which blotches of pale brown skin appear on the face. It is usually caused by hormonal changes. The blotches may appear in the forehead, cheeks, and nose, and may merge into one dark mask. It usually fades gradually after pregnancy, but it may become permanent or recur with subsequent pregnancies. Some women may also find that the line running from the top to the bottom of their abdomen darkens. This is called the linea nigra.
Mentioned in: Pregnancy
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
"Many changes are unavoidable during pregnancy - and most disappear on their own after delivery." The following are normal conditions during pregnancy Acne Bluish or blotchy legs Chloasma or pregnancy mask (hyperpigmentation of the skin) Glowing skin Itchiness Linea Nigra (a dark line on the belly) Nails and hair may grow faster than usual or become brittle or softer
Chloasma, oral contraceptives and plasma immunoreactive [beta]-Melanocyte Stimulating Hormone.
It is known as chloasma or melasma gravidarum, and comes in the form of blotchy areas of darkened skin that can appear on the face (sometimes in the shape of a mask) and on other parts of the body, like the forearms and legs.
The ocular adnexa can be affected by a condition known as chloasma, also called the 'mask of pregnancy' (see Figure 1).
It could be: 6 Chloasma, patches of increased pigmentation due to the high levels of MSH (melanocyte-stimulating hormone) which occur in pregnancy and lead to increased skin pigmentation.
Chloasma (Melasma) [online] 2009 [cited 2009 May 31].
Dianne has a condition called Chloasma, sometimes also known as melasma.
Q I've developed quite big brown patches on my cheeks and upper lip which have been diagnosed as melasma or chloasma. I've tried Skinoren, sunblock and fade-out cream, but none has worked.
REVIEW OF LITERATURE: The term "Melasma" is derived from the greek word "Melas" meaning "Black"and "Chloasma" from the greek word "Chloazein" meaning "to be green".
Also known as chloasma, these tanned patches on the face and neck are nicknamed `the mask of pregnancy', as they are common in pregnant women.
Like facial chloasma there is a sharp line of demarcation at the margins.
Chloasma of pregnancy, due to hormonal stimulation of the cells in the skin that produce melanin.