The short answer involves shared nerve pathways. The anal canal and the clitoris are both supplied by branches of the same nerve, the pudendal nerve, meaning stimulation in one area can activate pleasure circuits closely linked to the other. The anatomy turns out to be more interconnected than most people realize, with the internal portions of the clitoris physically extending toward the front wall of the rectum. But nerve wiring alone doesn’t explain the full picture, and not every woman experiences anal stimulation the same way.
The Pudendal Nerve Connects the Dots
The pudendal nerve originates from the lower spinal cord and splits into three branches: the dorsal clitoral nerve, the perineal nerve, and the rectal nerve. That last branch, sometimes called the inferior anal nerve, travels through the tissue alongside the anal canal to supply sensation to the external anal sphincter, the lower anal canal, and the surrounding skin.1Global Library of Women’s Medicine (GLOWM). Pudendal Neuralgia The key point is that all three branches share a common trunk. Signals traveling along the rectal branch are processed in the same spinal segments and brain regions as signals from the clitoral branch. This shared wiring means the brain doesn’t always draw a sharp line between “anal sensation” and “genital sensation.” Stimulation of the anal canal can activate overlapping neural territory, which is one reason the experience can register as sexually pleasurable rather than purely functional.
A recent anatomical mapping study found that the superficial anterior wall of the rectum, the side facing the front of the body, was the most frequently selected site of pleasure during receptive anal intercourse for both men and women.2Oxford University Press. Anal sex practices and rectal erogenous zone maps among men and women of diverse sexual orientations: an anatomic-map based questionnaire study The researchers proposed that this pattern lines up with the pudendal nerve’s route along the anterior aspect of the anal canal. In women specifically, there’s an additional factor: the internal extensions of the clitoris, sometimes called the clitoral legs or crura, reach toward the front wall of the rectum. Pressure on the anterior rectal wall during penetration may stimulate both the pudendal nerve path and these clitoral structures simultaneously.3Oxford University Press. Anal sex practices and rectal erogenous zone maps among men and women of diverse sexual orientations: an anatomic-map based questionnaire study
The Clitoris Is Bigger Than You Think
Most of the clitoris is internal. The visible glans is a small external tip, but underneath the skin, the clitoral body extends backward and then splits into two legs (crura) that flare along the pubic bone, plus two bulbs of erectile tissue flanking the vaginal opening. A meta-analysis of clitoral anatomy found that the average distance from the clitoris to the anus is about 76 millimeters, while the distance to the vaginal opening is about 43 millimeters.4PubMed Central. Beyond the tip of the iceberg: A meta-analysis of the anatomy of the clitoris Those numbers sound like the anus is far from the action, but they measure from the external glans. The internal legs of the clitoris extend considerably further back, toward the rectum, narrowing the functional gap.
The anterior vaginal wall is also relevant. Imaging studies have shown that during penetration, the vagina inflates and stretches the root of the clitoris, pressing the clitoral tissue against the vaginal wall with only a few millimeters of separation.5PubMed Central. G-spot: Fact or Fiction?: A Systematic Review Because the anterior vaginal wall and the anterior rectal wall are separated by a thin layer of tissue called the rectovaginal septum, pressure applied from inside the rectum can transmit through to the same region. This is why some women describe the sensation of anal penetration as including a sense of vaginal or clitoral involvement, even with no direct vaginal contact. The anatomy is packed tightly enough that stimulating one structure often involves its neighbors.
Erogenous Zones Inside the Anal Canal
Not all parts of the anal canal are equally sensitive. Research mapping erogenous sensation during receptive anal intercourse found that women reported greater pleasure from stimulation of the superficial anterior wall (about 18% of respondents selected it) and the superficial posterior wall (about 11%).6Oxford Academic. ORGASM ABILITY AND MAPPED EROGENOUS SENSATION DURING RECEPTIVE VAGINAL AND ANAL INTERCOURSE The anterior dominance makes anatomical sense given the pudendal nerve route and clitoral proximity discussed above. The posterior wall’s contribution is less straightforward but may involve other sensory nerve branches or pressure effects on the pelvic floor muscles.
There’s also a structure some researchers have called the “female prostate” or the paraurethral glands (historically known as Skene’s glands), which sit near the anterior vaginal wall. These glands share tissue characteristics with the male prostate, and some researchers have proposed they play a role in sexual sensitivity in that region.7The Journal of Sexual Medicine. 047 Review of the Evidence of the Female Prostate as a Functional Gland Whether anal penetration can stimulate these glands through the rectovaginal septum remains an open question, but the proximity is close enough that indirect pressure is plausible.
Orgasm During Anal Sex and the Role of Costimulation
Can women actually orgasm from anal intercourse? Some can, but the picture is more complicated than a simple yes or no. Survey data from a study of cisgender women found that about 19% reported being able to orgasm from receptive anal intercourse alone, without any additional stimulation. Half reported they could orgasm during anal sex but only with simultaneous clitoral or vaginal touch, and about 31% said they could not orgasm during anal intercourse regardless of what else was happening.6Oxford Academic. ORGASM ABILITY AND MAPPED EROGENOUS SENSATION DURING RECEPTIVE VAGINAL AND ANAL INTERCOURSE The researchers emphasized that costimulation, meaning touching the clitoris or vagina at the same time, was the dominant path to orgasm for most women during anal sex.
A U.S. probability sample of women aged 18 to 93 found similar themes: anal touch paired with simultaneous vaginal or clitoral touch worked synergistically, enhancing pleasure and orgasm beyond what either stimulus produced alone.8PubMed Central. Women’s techniques for pleasure from anal touch: Results from a U.S. probability sample of women ages 18–93 This makes sense given the shared nerve supply. Activating multiple branches of the pudendal nerve at once, or combining pudendal stimulation with direct clitoral contact, creates a broader pattern of nerve activation than any single stimulus could.
There is also physiological evidence that the pelvic floor muscles treat vaginal and anal stimulation as part of the same event. A study measuring muscle contractions during orgasm found that vaginal and anal contractions were synchronized with each other. The same number of rhythmic contractions occurred in each area, beginning near the perceived start of orgasm.9SpringerLink. The female orgasm: pelvic contractions The pelvic floor doesn’t distinguish between vaginal and anal muscle groups during climax; they fire together as a coordinated system.
The Neurochemistry Behind the Pleasure
The subjective feeling of pleasure during sexual activity, including anal stimulation, involves more than just nerve impulses reaching the brain. The brain’s reward circuitry releases dopamine and oxytocin during sexual arousal, ramping up desire and the feeling of being “turned on.” Orgasm then triggers a large release of opioids into these same brain regions, which dampens the dopamine and oxytocin signals but kicks off molecular changes that make the brain more responsive to those same chemicals in the future.10Oxford Academic (Sex Medicine Reviews). Orgasms, sexual pleasure, and opioid reward mechanisms This cycle of arousal, climax, and neurochemical reset helps explain why positive sexual experiences become self-reinforcing over time. If anal stimulation contributes to orgasm, the reward circuitry treats it as part of the pleasurable experience and reinforces it.
Oxytocin specifically appears to correlate with orgasmic capacity. Research has found that women who experience orgasm during sex tend to have higher baseline oxytocin levels than women who do not, and orgasmic women showed increased oxytocin after sexual activity while anorgasmic women who reported unpleasant or stressful sexual activity did not.11Oxford University Press / Sexual Medicine. How Relevant is the Systemic Oxytocin Concentration for Human Sexual Behavior? A Systematic Review The takeaway is that the emotional context matters. Feeling safe, aroused, and engaged appears to create a neurochemical environment more conducive to pleasure. Feeling stressed, pressured, or uncomfortable does the opposite, regardless of which nerve pathways are being stimulated.
Beyond the Spinal Cord
One fascinating piece of the puzzle comes from research on women with complete spinal cord injuries. These women have no spinal nerve communication between their genitals and their brain, yet some can still experience orgasm from vaginal and cervical stimulation. Brain imaging showed that this happens because the vagus nerve, which runs directly from the pelvic organs to the brainstem without passing through the spinal cord, can carry sexual sensation independently.12Elsevier / PubMed Central. Brain activation during vaginocervical self-stimulation and orgasm in women with complete spinal cord injury: fMRI evidence of mediation by the vagus nerves The vagus nerve’s role in pelvic sensation is still being mapped, but its existence means the pudendal nerve isn’t the only pathway capable of transmitting sexually relevant signals from the pelvic region to the brain. This adds another possible route through which anal stimulation could generate pleasure, especially deep stimulation that reaches the rectum rather than just the anal canal’s superficial nerve endings.
The vagus nerve finding also underscores a broader point: sexual sensation in the pelvis is not a single-wire system. Multiple nerve pathways converge on the same brain areas from slightly different routes, and the brain integrates all of them into a unified experience. The redundancy may explain why some women find anal stimulation pleasurable even when it doesn’t seem like the “right” anatomy is being targeted. The nervous system has more than one way to get the signal where it needs to go.
Why It Hurts for Some Women
Pleasure during anal sex is far from universal. A narrative review found that about 72% of women who engage in anal intercourse have experienced some degree of pain, a condition called anodyspareunia.13PubMed Central. Pelvic Floor Disorders Due to Anal Sexual Activity in Men and Women: A Narrative Review The main contributors were an overactive pelvic floor, meaning the muscles were too tense and couldn’t relax sufficiently during penetration, along with emotional discomfort, insufficient lubrication, and the size of the penetrating partner. Some women specifically reported that they could not relax enough during the experience, which creates a vicious cycle: tension causes pain, pain causes more tension, and the body learns to associate anal stimulation with distress rather than pleasure.
The anal canal, unlike the vagina, doesn’t produce its own lubrication. The tissue lining the anus is also thinner and more delicate than vaginal tissue. These differences mean that what works fine during vaginal intercourse, both in terms of preparation and physical force, is not automatically transferable. The research on women’s motivations for anal sex has also documented that the experience often doesn’t occur under ideal conditions. A qualitative study of heterosexual women found that the most common context involved being intoxicated, and that a substantial portion engaged in it primarily to please a partner rather than because they desired it.14SpringerOpen / PubMed Central. Why Women Engage in Anal Intercourse: Results from a Qualitative Study That study focused on a specific population of drug-using women and shouldn’t be generalized too broadly, but it highlights that context, agency, and arousal matter enormously for whether the experience registers as pleasurable or painful.
The neurochemistry discussed earlier is relevant here, too. The oxytocin data showed that women who experienced stressful or unpleasant sexual activity did not get the same neurochemical reward as women who had positive experiences. Arousal primes the body for pleasure: blood flow increases to erectile tissues (including the clitoral structures near the rectum), the pelvic floor relaxes, and the brain’s pain-processing circuits dial down. Without adequate arousal, the same physical stimulation that might feel good in one context can feel uncomfortable or even painful in another.
Who Reports the Most Pleasure
Demographics and sexual orientation appear to influence both how commonly women engage in receptive anal intercourse and which rectal zones they find pleasurable. Women in a large survey were significantly more likely than men to report having engaged in receptive anal intercourse (34% vs. 24%), and gay women and men were more likely to have participated than their heterosexual counterparts. Bisexual men and women were significantly more likely to select the superficial anterior rectum as pleasurable, while heterosexual women were significantly less likely to do so.15Oxford Academic. Anal sex practices and rectal erogenous zone maps among men and women of diverse sexual orientations: an anatomic-map based questionnaire study
These patterns are hard to interpret purely in anatomical terms, since the nerve supply and clitoral anatomy don’t differ by sexual orientation. The more likely explanation involves experience and comfort. People who engage in anal stimulation more regularly, and who do so because they actively want to rather than because a partner expects it, may learn over time which angles and pressures feel good. They may also be more likely to use costimulation techniques, to communicate about what works, and to approach the experience with the kind of arousal and relaxation that the pelvic floor needs to cooperate. The anatomy provides the hardware, but the software matters just as much.
The Arousal and Pain Connection
There’s a commonly repeated idea that sexual arousal dramatically raises pain thresholds, which would help explain why anal penetration can feel good when you might expect it to hurt. The experimental evidence is less clear-cut. One controlled study measured women’s pain responses during a cold pressor test under different arousal conditions. Women who were sexually aroused showed a trend toward reduced pain sensitivity compared to a neutral condition, but the effect was small to medium in size and did not reach statistical significance.16PLoS One. The influence of sexual arousal on subjective pain intensity during a cold pressor test in women The direction of the finding matched what you’d expect, but it wasn’t strong enough to draw confident conclusions from a single study. Other research has shown more robust pain-reduction effects during orgasm specifically, which makes sense given the opioid release described earlier. But the pre-orgasm arousal phase alone may not provide as much analgesic cover as popular accounts suggest.
What this means practically is that arousal helps, but it probably isn’t a magic switch that turns off pain perception. Adequate preparation, including slow progression, generous lubrication, communication, and genuine desire, likely does more for comfort than counting on arousal to mask discomfort. The anatomy supports pleasure through specific nerve pathways, but those pathways also carry pain signals. The difference between the two outcomes depends heavily on how the tissue is treated.
Anatomy Varies from Person to Person
One reason the experience differs so much between individuals is that the underlying anatomy isn’t identical in everyone. The meta-analysis of clitoral dimensions found a range of measurements, not a single standard set of numbers, for the distance between the clitoris and surrounding structures.4PubMed Central. Beyond the tip of the iceberg: A meta-analysis of the anatomy of the clitoris Women whose clitoral legs extend further toward the rectum, or whose pudendal nerve branches take a slightly different route, may get more stimulation from anal penetration than women whose anatomy is configured differently. The same applies to the thickness of the rectovaginal septum, the depth of the pelvic floor muscles, and the density of nerve endings in the anal canal itself.
This variability is the honest answer to the question of why some women find anal sex intensely pleasurable while others get nothing from it, and still others find it painful. The nerve pathways are present in everyone, but the degree to which anal stimulation activates them depends on individual anatomy, the specific technique used, the level of arousal, the emotional context, and whether costimulation is happening at the same time. Framing it as universally pleasurable or universally uncomfortable misses what the evidence actually shows: a spectrum of responses shaped by biology and circumstance in roughly equal measure.
The Female Prostate and Ongoing Questions
Researchers have known about the paraurethral glands for over a century, with descriptions tracing back to Alexander Skene in the 1880s and references in the Kama Sutra centuries before that. These glands share tissue markers with the male prostate at the molecular level, including the same immunohistochemical staining patterns.7The Journal of Sexual Medicine. 047 Review of the Evidence of the Female Prostate as a Functional Gland Whether they serve a meaningful role in sexual pleasure remains genuinely debated. Some researchers argue that stimulation of the anterior vaginal wall, whether from inside the vagina or indirectly through the rectum, activates these glands and contributes to the sensation people associate with “G-spot” stimulation. Others remain skeptical, noting that the glands are small and variable in size between women.
The broader lesson from this and other anatomical debates is that female pelvic anatomy has been understudied for a long time, and the research is still catching up. Much of what we know about anal erogenous zones comes from studies published in just the last few years. The erogenous zone mapping work, the clitoral anatomy meta-analysis, and the costimulation data are all recent. Earlier generations of sex researchers tended to focus on vaginal and clitoral stimulation and largely ignored anal sensation in women, which left a gap in the literature that’s only now being filled. As the anatomy becomes better characterized, the reasons behind individual differences in pleasure will become clearer. For now, the evidence points firmly to shared nerve supply, clitoral proximity, pelvic floor coordination, and the brain’s reward system as the main ingredients, with everything else still under investigation.