Vulva and clitoris

What the vulva is

"Vulva" names the external genitals: mons pubis, outer labia (labia majora), inner labia (labia minora), the clitoris and its hood, the vestibule, the urethral opening and the vaginal opening. The vagina is the internal canal. The two words are not interchangeable, and the confusion has clinical consequences — people report symptoms in the wrong place and are examined in the wrong place.

The clitoris is mostly internal

The visible glans is a small fraction of the organ. MRI and cadaveric dissection work published by Helen O'Connell and colleagues (1998, 2005) mapped the full structure: glans, body (corpora), two crura extending 5–9 cm along the pubic arch, and paired vestibular bulbs of erectile tissue flanking the vaginal opening. Total length is commonly around 9–11 cm.

• The glans carries roughly 8,000 nerve endings by classic estimate; a 2022 study by Uloko et al. counted a mean of 10,281 myelinated nerve fibres in the human dorsal nerve of the clitoris, about 20 percent more than earlier figures.
• Erectile tissue engorges during arousal; the glans typically retracts under the hood near orgasm, which is normal and not withdrawal of interest.
• O'Connell's work showed the distal urethra, vagina and clitoris are anatomically bound together — a "clitoral complex". This is the anatomical basis for why the distinction between "vaginal" and "clitoral" orgasm is not structurally meaningful.

Normal variation

Labia vary enormously and asymmetry is the norm. Lloyd et al. (2005, BJOG) measured 50 premenopausal women: inner labia length ranged 20–100 mm and width 7–50 mm; clitoral glans length ranged 5–35 mm. A larger 2018 study by Kreklau et al. (BJOG, 657 women) found similar spread. There is no medically defined "too large".

Colour ranges from pink through brown to purple-grey and commonly darkens with puberty, pregnancy and age. Pubic hair pattern, mons prominence and vestibule appearance all vary.

The vagina

A muscular, collapsible canal, on average 7–10 cm at rest and lengthening with arousal (vaginal tenting). It is self-cleaning: lactobacilli maintain a pH of roughly 3.8–4.5. Douching disrupts this and is associated with bacterial vaginosis, pelvic inflammatory disease and preterm birth (Cottrell, 2010, review); no professional body recommends it.

The anterior wall region often described as the "G-spot" has no discrete anatomical structure on histology. Reviews by Hoag, Keast and O'Connell (2017) and Vieira-Baptista et al. (2021) conclude it is best understood as the area where the urethra, Skene's glands and the internal clitoris converge. Sensitivity there is real; a separate organ is not supported.

The hymen

A thin, variable membrane at the vaginal opening, usually crescentic with an open passage. It does not "break" once and it does not indicate sexual history. Reviews of examination evidence (Adams et al., 2016; WHO, 2018) found no reliable way to determine prior intercourse from hymenal appearance. WHO, the UN and the WMA jointly called for the elimination of virginity testing in 2018.

Lubrication

Arousal fluid comes from vaginal transudation plus Bartholin's and Skene's gland secretion. Volume varies with cycle phase, hydration, medication (antihistamines, some antidepressants, hormonal contraception), breastfeeding and menopause. Low lubrication is not a reliable measure of desire: arousal non-concordance — genital response and subjective desire not matching — is well documented, with a meta-analysis by Chivers et al. (2010) finding a correlation of only about r = 0.26 in women versus about r = 0.66 in men. Use lubricant freely; it is not a failure.

Care

• Wash the vulva with warm water or plain unfragranced cleanser; do not wash inside the vagina.
• Cotton underwear and avoiding prolonged damp fabric reduce irritation.
• See a clinician for: new lumps, persistent itch, ulcers, unusual bleeding, discharge with odour or colour change, or pain that does not settle. Persistent vulval itch in older adults can indicate lichen sclerosus, which is treatable and is associated with a small vulval cancer risk if untreated.

Sources

• O'Connell HE, Sanjeevan KV, Hutson JM. "Anatomy of the clitoris." Journal of Urology, 2005.
• O'Connell HE et al. "Anatomical relationship between urethra and clitoris." Journal of Urology, 1998.
• Uloko M et al. "How many nerve fibers innervate the human glans clitoris?" Journal of Sexual Medicine, 2023.
• Lloyd J et al. "Female genital appearance: 'normality' unfolds." BJOG, 2005.
• Kreklau A et al. "Measurements of a 'normal vulva' in women aged 15–84." BJOG, 2018.
• Hoag N, Keast JR, O'Connell HE. "The 'G-spot' is not a structure evident on macroscopic anatomic dissection." Clinical Anatomy, 2017.
• Vieira-Baptista P et al. "G-spot: fact or fiction? A systematic review." Sexual Medicine, 2021.
• Chivers ML et al. "Agreement of self-reported and genital measures of sexual arousal: a meta-analysis." Archives of Sexual Behavior, 2010.
• WHO/OHCHR/UN Women. "Eliminating virginity testing: an interagency statement." 2018.
• Royal College of Obstetricians and Gynaecologists. Green-top and patient guidance on vulval skin disorders, current edition.

Last reviewed: August 2026.