Labia minora

Labia minora

Labia minora (inner labia)
Details
Precursor Urogenital folds
Identifiers
Latin labium minus pudendi
Dorlands
/Elsevier
Labia minora pudendi
TA A09.2.01.007
FMA 20374

Anatomical terminology

The labia minora (singular: labium minus), also known as the inner labia, inner lips, vaginal lips or nymphae,[1] are two flaps of skin on either side of the human vaginal opening in the vulva, situated between the labia majora (outer labia, or outer lips). Inner lips vary widely in size, color, and shape from individual to individual.

Structure

The inner lips extend from the clitoris obliquely downward, laterally, and backward on either side of the vulval vestibule, ending between the bottom of the vulval vestibule and the outer lips. The posterior ends (bottom) of the inner lips are usually joined across the middle line by a fold of skin, named the frenulum of labia minora or fourchette.

On the front, each lip forks dividing into two portions surrounding around the clitoris. The upper part of each lip passes above the clitoris to meet the upper part of the other lip—which will often be a little larger or smaller—forming a fold which overhangs the glans clitoridis; this fold is named the clitoral hood. The lower part passes beneath the glans clitoridis and becomes united to its under surface, forming, with the inner lip of the opposite side, the frenulum clitoridis.

Histology

On the opposed surfaces of the labia minora are numerous sebaceous glands not associated with hair follicles. They are lined by stratified squamous epithelium on those surfaces.[2]

Variation

Human vulva with anatomical feature labels

From 2003 to 2004, researchers from the Department of Gynaecology, Elizabeth Garret Anderson Hospital in London, measured the labia and other genital structures of 50 women from the age of 18 to 50, with a mean age of 35.6. The results were:[3]

Measuring Range Mean [SD]
Clitoral length (mm) 5–35 19.1 [8.7]
Clitoral glans width (mm) 3–10 5.5 [1.7]
Clitoris to urethra (mm) 16–45 28.5 [7.1]
Labia majora length (cm) 7.0–12.0 9.3 [1.3]
Labia minora length (mm) 20–100 60.6 [17.2]
Labia minora width (mm) 7–50 21.8 [9.4]
Perineum length (mm) 15–55 31.3 [8.5]
Vaginal length (cm) 6.5–12.5 9.6 [1.5]
Tanner stage (n) IV 4
Tanner stage (n) V 46
Colour of genital area
compared with surrounding skin (n)
Same 9
Colour of genital area
compared with surrounding skin (n)
Darker 41
Rugosity of labia (n) Smooth 14
Rugosity of labia (n) Moderate 34
Rugosity of labia (n) Marked 2

In female anatomy macronymphia is the term used for an abnormally large labia minora commonly found as a racial characteristic in certain ethnic groups such as Khoisans.[4]

Additional images

See also

References

  1. nymphae. Dictionary.com. Merriam-Webster's Medical Dictionary. Merriam-Webster, Inc. (accessed: November 24, 2007).
  2. Manual of Obstetrics. (3rd ed.). Elsevier. pp. 1-16. ISBN 9788131225561.
  3. Lloyd, Jillian et al. "Female genital appearance: 'normality' unfolds", British Journal of Obstetrics and Gynaecology, May 2005, Vol. 112, pp. 643–646. PMID 15842291
  4. Cruciani, F; Santolamazza, P; Shen, P; Macaulay, V; Moral, P; Olckers, A; Modiano, D; Holmes, S; Destro-Bisol, G; Coia, V; Wallace, DC; Oefner, PJ; Torroni, A; Cavalli-Sforza, LL; Scozzari, R; Underhill, PA (May 2002). "A back migration from Asia to sub-Saharan Africa is supported by high-resolution analysis of human Y-chromosome haplotypes.". American Journal of Human Genetics 70 (5): 1197–214. doi:10.1086/340257. PMC 447595. PMID 11910562. Cite uses deprecated parameter |coauthors= (help)
This article is issued from Wikipedia - version of the Saturday, April 30, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.