Table of Contents
Ask most adults to draw a complete, accurate diagram of the clitoris, and very few will get much further than a small external structure. That's not really their fault. A full anatomical description of the clitoris, built from dissection, microdissection, and MRI, was not published until 2005, meaning most people currently alive were educated using diagrams that were already known to be incomplete. This lesson works through both external and internal genital structures for both sexes, using research that in several cases is newer than most people's original sex education.
External Female Anatomy: The Vulva
The vulva refers to the external female genital structures as a whole, including the labia majora (the outer folds), the labia minora (the inner folds), the clitoral hood, the vestibule containing the urethral and vaginal openings, and the area between the vaginal opening and the anus known as the perineum. Despite common usage, "vagina" technically refers only to the internal canal, not the external structures collectively, a distinction that gets blurred constantly in casual conversation.
The Clitoris Is Mostly an Internal Structure
What's visible externally, the glans, is only a small portion of a much larger structure. Urologist Helen O'Connell and colleagues at the University of Melbourne published the first comprehensive anatomical account of the clitoris in 2005, combining MRI imaging of healthy volunteers with cadaveric dissection. Their findings confirmed that the clitoris is a multiplanar structure consisting of a non-erectile tip, the glans, along with erectile bodies, specifically the paired bulbs, crura, and corpora, all of which maintain a consistent anatomical relationship to the urethra and vagina (O'Connell, Sanjeevan, & Hutson, 2005).
In practical terms, the clitoris includes six main components: the glans, the suspensory ligament, the body (corpora), the root, the paired crura, and the paired vestibular bulbs, with the internal portion accounting for most of the structure's actual mass (O'Connell et al., 2005). The glans itself is densely innervated, with subsequent research describing more than 8,000 nerve endings concentrated in this small visible portion alone (O'Connell et al., 2008, as cited in a later anatomical summary). A 2024 meta-analysis revisiting this literature noted that despite the clitoris being widely recognized as the structure most critical to sexual arousal and orgasm in women, remarkably few anatomical studies of it have ever been conducted, only 11 dissection-based studies published worldwide since 1947 (Longhurst et al., 2024).
Just How Much Do Genitals Actually Vary?
A great deal of unnecessary anxiety about genital appearance comes from a simple lack of reference data: most people have only ever seen their own body and a narrow, often airbrushed, range of images elsewhere. In 2005, researcher Jillian Lloyd and colleagues in London conducted one of the first studies to systematically measure genital dimensions in a group of 50 premenopausal women, examining clitoral size, labial length and width, color, texture, and vaginal length. Their conclusion was direct: women varied greatly across every genital measurement studied (Lloyd, Crouch, Minto, Liao, & Creighton, 2005).
A follow-up study extending this research to adolescents found the variability was, if anything, even more pronounced at younger ages. Examining 44 adolescents between ages 10 and 19, researchers found that labial size, color, and texture showed no relationship to chronological age, pubertal stage, height, weight, or ethnicity (Brodie et al., 2019). The same study found that asymmetry between the left and right labia minora was itself entirely typical, present in 43% of the adolescents studied, with differences in width ranging as high as 22 millimeters between sides (Brodie et al., 2019). A separate cohort study examining the relationship between genital anatomy and sexual function found wide disparities in every measured parameter, but no association between genital dimensions and sexual function itself (anatomical diversity study, 2015). Comparable studies conducted in Thai, Iranian, and South Indian populations have each independently confirmed the same core finding: wide, statistically normal variation with no established single template for what a "normal" vulva should measure (regional normal-variation studies, 2020 to 2025).
| Finding | Source |
|---|---|
| Wide variation in labial length, width, color, and texture among adult women | Lloyd et al., 2005 |
| No correlation between labial size and age, weight, height, or ethnicity in adolescents | Brodie et al., 2019 |
| Left-right labial asymmetry present in 43% of adolescents studied | Brodie et al., 2019 |
| No association found between genital dimensions and sexual function | Anatomical diversity cohort study, 2015 |
Internal Female Anatomy
Moving inward from the vaginal opening, the vagina is a muscular, elastic canal lined with folds called rugae, which allow it to expand considerably during arousal, penetration, or childbirth. At its upper end sits the cervix, the narrow lower portion of the uterus, which contains a small canal connecting the vaginal canal to the uterine cavity. This is also worth noting plainly: the thin tissue partially covering the vaginal opening in some people, commonly called the hymen, varies enormously in shape and does not reliably indicate anything about a person's sexual history, a point formally confirmed by the World Health Organization, the UN Human Rights Office, and UN Women in a joint 2018 statement rejecting so-called virginity testing on exactly this anatomical basis (WHO, OHCHR, & UN Women, 2018).
External Male Anatomy
The external male genitalia consist of the penis and scrotum. The penis includes the glans (the sensitive tip), the shaft, and, in uncircumcised men, the foreskin (prepuce), a retractable fold of skin covering the glans. The scrotum, a pouch of skin behind the penis, houses the testes and helps regulate their temperature, since sperm production requires a temperature slightly below core body temperature.
Penis size is one of the most anxiety-inducing topics in this entire area of anatomy, almost entirely due to a lack of accurate reference data rather than any genuine medical concern for most men. In 2015, researcher David Veale and colleagues at King's College London conducted the largest systematic review to date, pooling data from 17 studies and more than 15,000 men measured by health professionals using standardized procedures, specifically excluding men with any penile abnormality or complaint about size. Their analysis produced the first reliable nomograms, or normal-range charts, for penis size: a mean flaccid length of 9.16 cm, a mean flaccid stretched length of 13.24 cm, and a mean erect length of 13.12 cm (Veale, Miles, Bramley, Muir, & Hodsoll, 2015). The strongest correlation found in the entire dataset was a modest one, between stretched or erect length and a man's height, ranging from a correlation of 0.2 to 0.6 (Veale et al., 2015). The researchers stated their purpose explicitly: to help reassure the large majority of men that their own measurements fall within the normal range charted by the study (Veale et al., 2015).
Internal Male Anatomy
Internally, each testis contains tightly coiled seminiferous tubules, which is where sperm cells are actually produced, surrounded by supportive Sertoli cells and hormone-producing Leydig cells. From there, sperm travel to the epididymis for maturation, then through the vas deferens toward the urethra, picking up fluid contributed by the seminal vesicles and prostate gland along the way to form semen.
Almost nobody's body matches the single mental image they grew up with. That's not a flaw in any particular body. It's a flaw in the mental image.
A line worth remembering the next time comparison creeps in
Common Misunderstandings, Cleared Up
"Is the clitoris just the small visible part at the top of the vulva?"
No. MRI and dissection research confirms the visible glans is only a small portion of a much larger, mostly internal structure that includes paired bulbs, crura, and a body extending well beneath the surface (O'Connell et al., 2005).
"If my labia look asymmetrical, is something wrong?"
No. Research specifically measuring this found asymmetry between the two sides in 43% of adolescents studied, with meaningful size differences considered entirely typical rather than a sign of any problem (Brodie et al., 2019).
"Doesn't penis size significantly affect sexual satisfaction or function?"
Research examining genital dimensions broadly, across multiple studies of both male and female anatomy, has not found a meaningful association between size and sexual function (anatomical diversity cohort study, 2015). The nomogram research on penis size was explicitly designed to reassure men that a wide range of measurements is statistically normal (Veale et al., 2015).
Applying This Practically
- Recognize that visible or measurable genital variation, in both appearance and size, is the well-documented norm across every population studied, not the exception.
- Be cautious about comparing personal anatomy to media or pornographic images, which are typically drawn from a narrow, unrepresentative range rather than reflecting the studied normal distribution.
- Learn the actual internal structures relevant to your own body, since accurate anatomical knowledge, rather than a vague or incomplete mental picture, supports both better communication with partners and better communication with healthcare providers.
- Reserve genuine concern for changes in sensation, pain, or function, rather than appearance or size alone, and raise those specific changes with a qualified clinician.
References
Brodie, K. E., et al. (2019). A study of adolescent female genitalia: What is normal? Journal of Pediatric and Adolescent Gynecology, 32(1), 27–31.
Lloyd, J., Crouch, N. S., Minto, C. L., Liao, L. M., & Creighton, S. M. (2005). Female genital appearance: "Normality" unfolds. BJOG: An International Journal of Obstetrics & Gynaecology, 112(5), 643–646. https://doi.org/10.1111/j.1471-0528.2004.00517.x
Longhurst, C., et al. (2024). Beyond the tip of the iceberg: A meta-analysis of the anatomy of the clitoris. Clinical Anatomy, 37(4), 391–404. https://doi.org/10.1002/ca.24113
O'Connell, H. E., Sanjeevan, K. V., & Hutson, J. M. (2005). Anatomy of the clitoris. Journal of Urology, 174(4, Pt 1), 1189–1195. https://doi.org/10.1097/01.ju.0000173639.38898.cd
Veale, D., Miles, S., Bramley, S., Muir, G., & Hodsoll, J. (2015). Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15,521 men. BJU International, 115(6), 978–986. https://doi.org/10.1111/bju.13010
World Health Organization, UN Human Rights Office (OHCHR), & UN Women. (2018). Eliminating virginity testing: An interagency statement.