Linea nigra
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Linea nigra (Latin for "black line") is a dark vertical line that appears on the abdomen during about three quarters of all pregnancies.[1] The brownish streak is usually about a centimeter in width. The line runs vertically along the midline of the abdomen from the pubis to the xiphoid process.[2]
It is a type of hyperpigmentation resulting from increased production of the pigment melanin thought to be caused by increased estrogen, the same process that causes the areolas to darken.[3][4] Why this process of hyperpigmentation occurs on the midline of the abdomen is uncertain. Fair-skinned women show this symptom less often than women with darker pigmentation[citation needed]. Before it appears it may be more faintly visible as a linea alba ("white line").[citation needed]
Linea nigra tends to appear around the second trimester. After birth, the line fades slowly, but may never disappear entirely, and sun exposure may cause it to recur.[4]
[edit] See also
[edit] References
- ^ Estève E, Saudeau L, Pierre F, Barruet K, Vaillant L, Lorette G (1994). "[Physiological cutaneous signs in normal pregnancy: a study of 60 pregnant women]" (in French). Ann Dermatol Venereol 121 (3): 227–31. PMID 7832550.
- ^ She Knows Network: "What's that line? All about linea nigra"
- ^ George AO, Shittu OB, Enwerem E, Wachtel M, Kuti O (May 2005). "The incidence of lower mid-trunk hyperpigmentation (linea nigra) is affected by sex hormone levels". J Natl Med Assoc 97 (5): 685–8. PMID 15926645.
- ^ a b Parents Magazine
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