Quickies: Sexual Anatomy

Sexual anatomy⁠ (anatomy: The body, parts of the body, or physical structure of organisms like people, animals or plants.) is about far more than genitals⁠ (genitals: Body parts that are generally, culturally, scientifically or personally considered to be external sexual or reproductive organs.) . We can explore and experience our sexuality and pleasure with potentially all the parts of the body.

Here are some of the body parts most often involved when people explore sexuality and seek pleasure.

The brain: The largest, most important and most active sexual⁠ (sexual: About or relating in some way to sex or sexuality.) organ of the body isn’t a penis⁠ (penis: One of the two external reproductive organs of people often assigned male at birth.) or vagina⁠ (vagina: The internal passage leading from the opening of the vulva to the cervix of the uterus.) . It’s the brain!

Sexuality is usually about the body. It’s also just as much about thoughts and feelings. Even in the ways it is physical, we feel those sensations through our central nervous system⁠ (nervous system: The system of cells, tissues and organs that regulate our body's responses to internal and external stimuli.) . That’s all brain stuff. Without a brain, we couldn’t experience sexuality or pleasure.

The brain also releases hormones⁠ (hormones: Chemicals – via our endocrine system – that send messages across our bodies and brains. They both naturally exist and can also be made in a lab.) that influence how sex⁠ (sex: Different things people choose to do to actively express or enact sexuality and sexual feelings; often this involves genitals, but not always. ) feels. All of our body parts are communicating with the brain during sex. The brain is also primarily responsible for orgasm⁠ (orgasm: An event typically in response to physical or intellectual sexual stimulation, controlled by the involuntary nervous system. ) and is where orgasm actually happens.

Erogenous zones: Erogenous zone is a term used to describe a part of the body that usually feels extra sensitive. That’s because it’s got a lot of sensory nerve endings. This can include the lips, tongue, palms and fingers, the bottoms of the feet, the inner thighs, nipples, neck, ears, armpits and the genitals.

The perianal⁠ (perianal: Around the anus.) region (the butt): The anus⁠ (anus: The external opening to the rectum, located between the buttocks.) is the opening (to the rectum⁠ (rectum: The internal passage between the anus and the colon; stores solid waste until it leaves the body through a bowel movement.) , inside the body) that’s visible between your buttocks. It and the rectum can be sites of sexual pleasure for people of any gender⁠ (gender: Characteristics that are seen or presented as distinguishing between male and female in a society. Gender may or may not include assigned or chosen: social roles, feelings, behaviors and/or presentation or appearance.) or sexual orientation⁠ (sexual orientation: A term -- like homosexual, heterosexual, bisexual, queer, straight, lesbian, gay, asexual -- used to describe a person's usual or current pattern of emotional, romantic and/or sexual attraction to other people as it relates to or is about gender.) . Then there’s the prostate. The prostate is a walnut-sized gland in the body that’s located below the bladder. If you were born with a penis, you were probably born with a prostate. The prostate is very sensitive to pressure and touch. It can be pleasurable to have it stimulated.

The pudendal nerve is also located in this area, at the bottom⁠ (bottom: Either a colloquial term for buttocks or even the whole genital area, or someone who wants to consensually relinquish control or active leadership during sex to a partner and follow their lead.) of the spine. A lot of the feelings people have in their genitals during orgasm and other parts of sexual response are because of the pudendal nerve talking to the brain.

The pubococcygeus muscle (which some people might call PC or Kegel muscles) is also in this area. It stretches from the pubic bone to the tailbone. It supports the pelvic organs. It usually contracts during orgasm.

The perineal sponge is also in this region for people born with a vulva⁠ (vulva: The name for the external genitals of people assigned female at birth. The vulva includes the mons, external clitoris, inner and outer labia, fourchette and perineum.) (that's all the outside portions of the genitals for someone with a vagina). It’s internal to the body, between the bottom of the  vaginal opening⁠ (vaginal opening: The external opening to the vagina.)  and the rectum. It’s part of the clitoral system. It is made of nerve endings, erectile tissue and blood vessels. A person might feel sensations of this sponge from stimulation to the vagina, clitoris⁠ (clitoris: A sexual organ both external and internal on the vulva and inside the pelvis of those often assigned female at birth that is similar to the penis, but serves no other known purpose besides providing sexual pleasure.) or anus or the areas around them.

The penis: Any and all parts of the penis may be enjoyable—or not!—when touched during sex or masturbation⁠ (masturbation: Ways that people seek out and/or experience sexual pleasure by themselves, without a sexual partner.) . The head of the penis usually has a higher number of sensory nerves than the shaft⁠ (shaft: On the penis, the portion of the penis extending from below the head to the base of the penis, where it is attached to the body. On the vulva, an internal portion of the clitoris behind and beneath the clitoral glans.) . If a person with a penis has a foreskin⁠ (foreskin: A loose tube of skin with nerve endings that extends from shaft of the penis to below the glans and which normally covers the head of the penis when it is not erect. ) , that can also be a source of pleasure. It’s full of sensory nerve endings. The testes⁠ (testes: Reproductive glands of people with penises. They sit outside the body and are contained within the scrotum.) and scrotum also have many sensory nerve endings. People can find sexual enjoyment through stimulation of their scrotum or testicles.

The clitoris: The clitoris is similar to the penis.

It is the only part of the body whose only known purpose is pleasure. The clitoral shaft is on the outside of the body, above the urinary opening within the vulva. This is what most people call the whole clitoris. That’s only one part of a much larger system that has parts both inside and outside the body. The  crura⁠ (crura: The internal "legs" of the clitoris, which are within the outer labia (labia majora).) , the corpus carvernosum, the urethral sponge and the vestibular bulbs⁠ (vestibular bulbs: Two portions of erectile tissue that are part of the internal clitoris. As with the penis, erection can occur within the vulva due to these bulbs. Sometimes called the clitoral bulbs.) are all on the inside of the body. They are also parts of the clitoris that can provide pleasure.

The vagina: The vagina is a muscular tube inside the body. On one end of it is the vaginal opening, the place where things can go inside. On the other the end, inside the body, it ends at the cervix⁠ (cervix: The opening to the uterus, the bottom of which is at the back end of the vagina.) , which is the opening to the uterus⁠ (uterus: An internal, muscular reproductive organ in the pelvis. During pregnancy, this is where a fetus will develop. The lining of a person’s uterus is also the thing that sheds every menstrual cycle in what we call a period.) . The majority of nerve endings in the vagina are in the first third of it closer to the opening. You may have heard of the “G-spot” inside the vagina. The G-spot is also part of the clitoral system and is within that first third of the vagina. Touching that area can be pleasurable. The back two-thirds of the vagina aren’t very sensitive. This is one reason why people with vaginas usually won’t reach orgasm or experience a lot of pleasure from vaginal intercourse⁠ (vaginal intercourse: When a penis or sex toy is inserted into and held by the vagina while partners move their bodies as feels good to them for the purpose of either sexual stimulation and/or reproduction.) alone.

The labia⁠ (labia: On the vulva, both inner (labia minora) and outer (labia majora) sets of skin with sensory nerve endings which surround the vaginal opening.) and mons⁠ (mons: A mound of fatty tissue (skin) covering the upper portion of the vulva. In adult people, this area is usually where much of the pubic hair is.) : The mons, the part of the vulva where most of the pubic hair⁠ (pubic hair: The hair that grows around the genital and anal regions (often extending a ways up the front or back and onto the inner thighs) and usually first appears around puberty. It may vary in color, texture, length, and thickness.) is, has sensory nerve endings. The labia are the parts that look like lips or folds of skin. They are also very sensitive. Because of how everything fits closely together in the genitals, touching these body parts can also stimulate the parts of the clitoris.

Not everyone’s genitals or other body parts behave the same way. Not everyone likes or feels the same things or areas of the body in the same way.

What feels good to one person during sex or masturbation can, and often will, change over time. It also won’t always feel the same way with one partner⁠ (partner: In a sexual context, a person with whom someone is having some kind of sex. The term "partner" can be used for all kinds of relationships, not just serious ones. "Partner" can also mean the person someone is with in a romantic or familial partnership.) as it does with another. What feels good varies from person to person. That’s one reason it’s important for partners to talk to each other about what feels good during sex. Even though we all have the same or very similar body parts and systems, we each experience sex in a unique way.

To find out⁠ (out: Short for ‘out of the closet’. When someone’s LGBTQ+ identity is known to other people.) more about sexual anatomy and related topics:

• To read the longer article this piece is a summary of: With Pleasure: A View of Whole Sexual Anatomy for Every Body, by Heather Corinna
• To learn more about the penis: Innies & Outies: The Penis, Testes, and More
• To learn more about the vagina and surrounding: Innies & Outies: The Vagina, Clitoris, Uterus, and More
• For advice on what to do if you’re worried about penis size: Shown Actual Size: A Penis Size and Shape Lowdown
• To learn how different labia can look: Give ‘em Some Lip: Labia that Clearly Ain't Minor
• To learn about sexual response and orgasm: Sexual Response and Orgasm: A Users Guide
• To learn why slowing down can increase pleasure: Yield for Pleasure
• To learn more about the prostate: Meet Your Prostate
• To learn more about the foreskin: A Foreskin Foray: Questions, Concerns, and Clarifications
• To learn how to talk to a partner about what feels good: Be a Blabbermouth: The Whys, Whats, and Hows of Talking About Sex with a Partner
• To learn what to do if sex is painful: From Ow! to Wow! Demystifying Painful Intercourse

Some resources on sexual anatomy outside Scarleteen:

• The Penis Book by Joseph Cohen
• The Orgasmic Mind at Scientific American
• Learn about the clitoris and pleasure at Sex, Etc.
• Where is the Clitoris? at Go Ask Alice
• More information on the prostate at Teen Health Source

Teachers, caregivers, therapists, peer educators and other sex and relationships education providers: you're welcome to use the PDF handout version of this article for free, in any of the work you do, so long as it is provided to learners at no cost, is not used for profit, and you print it exactly as provided, including the copyright and other attribution.