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Linea nigra


Linea nigra (Latin for "black line") is a skin pigment condition during pregnancy where a brownish streak less than a centimeter in width develops. The line runs vertically along the midline of the abdomen from the pubis to the xiphoid process - the bottom-most part of the rib cage in the center or tip of the sternum.

It is caused by pregnancy hormones that increase production of the pigment melanin. This is also known as hyperpigmentation. Fair skinned women show this symptom less often than women with darker pigmentation.

Linea nigra tends to appear around the second trimester. Some research suggests there may be a link between linea nigra and insulin. Supplementing the diet with folic acid is said to reduce the discoloration.

There is an old wives' tale associated with linea nigra: if the linea nigra runs to the navel, it's a girl, and if it goes all the way up to the xiphoid, it's a boy.

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07-14-2008 23:18:10
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