Linea nigra

From Infogalactic: the planetary knowledge core
Jump to: navigation, search
Linea nigra as seen in a pregnant woman
A Cesarean section scar (horizontal red line) and linea nigra visible on a 31-year-old woman 7 weeks after childbirth.

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 umbilicus, but can also run from the pubis to the top of the abdomen.[2] Linea nigra is due to increased melanocyte-stimulating hormone made by the placenta,[3] which also causes melasma and darkened nipples.

Fair-skinned women show this phenomenon less often than women with darker pigmentation.[4] Linea nigra typically disappears within a few months after delivery.

See also


  1. 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]". Ann Dermatol Venereol (in French). 121 (3): 227–231. PMID 7832550. <templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
  2. She Knows Network: "What's that line? All about linea nigra"
  3. Heffner, Linda (2010). The Reproductive System at a Glance. Wiley-Blackwell. p. 51. ISBN 978-1-4051-9452-5.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
  4. Pregmed, Editor. "Linea nigra and pregnancy". Pregmed. Retrieved 22 February 2015.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>

Media related to Linea nigra at Wikimedia Commons