Where Is the Prostate Located and What Does It Do?

The prostate gland sits deep in the male pelvis, just below the bladder and directly in front of the rectum. It wraps around the upper portion of the urethra, the tube that carries urine from the bladder out through the penis. About the size of a walnut in younger men, this small gland punches above its weight in clinical importance because of its location at the crossroads of the urinary and reproductive systems.

Exact Position in the Pelvis

If you picture the male pelvis as a bowl, the prostate sits near the bottom, nestled behind the pubic bone and in front of the rectum. The bladder rests directly on top of it, and the urethra passes straight through its center like a tunnel through a hill. This is not just a casual anatomical detail. Because the prostate encircles the urethra, any swelling of the gland can squeeze the urinary channel and make it harder to urinate. That relationship between the prostate and the urethra is why urinary symptoms are so often the first sign of prostate trouble.

The gland’s back surface lies against the front wall of the rectum, separated by only a thin layer of tissue. That closeness is what makes a digital rectal exam possible: a doctor can reach the prostate through the rectal wall and feel its size, shape, and firmness. One study defining a “complete” digital rectal exam described the upper border of the prostate as the landmark used when examining the rectum, illustrating just how accessible the gland is from that approach.¹

Below the prostate, the pelvic floor muscles form a sling of support. The neurovascular bundles that control erections run along the sides and back of the gland, a detail that became critically important once surgeons began trying to spare those nerves during prostate cancer operations.² One anatomical study found that these bundles also have connections to the levator ani muscle and the anterior rectal wall, relationships that earlier descriptions had missed entirely.³

What Passes Through It

Two important pathways run through the prostate, and understanding them explains most of what the gland does and why its location causes problems when things go wrong.

The first is the prostatic urethra. This stretch of the urethra begins where the bladder neck opens and exits at the prostate’s tip, or apex. Every drop of urine you pass travels through this segment. So does semen during ejaculation, which is why the prostate is both a urinary and a reproductive organ.

The second set of structures are the ejaculatory ducts. These are formed by the union of the vas deferens (which carries sperm from each testicle) and the seminal vesicles (which add most of the fluid to semen). The ejaculatory ducts enter the prostate from its back surface, angle forward and toward the midline, and empty into the prostatic urethra at a small mound called the seminal colliculus.⁴ This junction is where prostatic fluid, sperm, and seminal vesicle fluid all converge before being propelled outward during ejaculation.

What the Prostate Actually Does There

The prostate’s job is to produce a portion of the fluid that makes up semen. Prostatic secretions are rich in enzymes, citrate, and lipids, and they contribute roughly a quarter of the total volume of seminal fluid. The seminal vesicles, which sit just above and behind the prostate, produce the largest share at about two-thirds of the volume.⁵ The enzymes from the prostate help liquefy semen after ejaculation, which is necessary for sperm to swim freely.

Smooth muscle fibers within the prostate also contract during ejaculation, helping to push fluid into the urethra. At the same time, the bladder neck above closes to prevent semen from flowing backward into the bladder. This choreography depends on everything being in the right place, and the prostate is quite literally at the center of it.

Internal Zones and Why They Matter

From the outside, the prostate looks like a single walnut-shaped lump. On the inside, it is divided into distinct zones, each with different tissue characteristics and different tendencies toward disease. The classic zonal model, established by researcher John McNeal, describes four regions organized around the urethra as a central reference point.⁶

Peripheral zone: The largest region, making up over 70% of the glandular tissue. Its ducts fan out from the urethra toward the back and sides of the gland. This is where the vast majority of prostate cancers originate, and it is the part a doctor feels during a rectal exam.
Central zone: Accounts for about 25% of the glandular tissue. It surrounds the ejaculatory ducts and sits at the base of the prostate, closest to the bladder. Its tissue looks distinctly different under a microscope from the peripheral zone, suggesting real biological differences between the two.
Transition zone: A smaller region immediately surrounding the urethra. Though modest in size in younger men, this is the zone that enlarges in benign prostatic hyperplasia, the non-cancerous growth that commonly causes urinary problems with aging.
Periurethral glands: Tiny ducts embedded in the tissue right next to the urethral lining. These are the smallest component and generally the least clinically significant.

The tissue composition of these zones differs in measurable ways. A histological study comparing the zones found that the transition zone has substantially more collagen, muscle fibers, and elastic tissue than the peripheral zone. The transition zone had about 40% more collagen and 47% more muscle fiber than the peripheral zone, and nearly 85% more elastic fibers.⁷ Those structural differences help explain why the transition zone behaves differently when it starts to grow.

These zones are not just academic curiosities. When a biopsy finds cancer, the zone of origin matters. One study found that targeted biopsy positivity for clinically significant cancer was roughly half as likely in transition zone lesions compared to peripheral zone lesions, at about 27% versus 55%.⁸ Knowing where within the prostate a suspicious area sits changes how doctors weigh the likelihood that it represents real cancer versus a false alarm.

How It Gets There in the First Place

The prostate develops during fetal life from a structure called the urogenital sinus, the precursor tissue that also gives rise to the bladder and parts of the urethra. Around the tenth to twelfth week of gestation, androgens (primarily testosterone) trigger the urogenital sinus to sprout small epithelial buds that grow, branch, and eventually hollow out to become the gland’s network of ducts.⁹ This process of ductal branching depends on androgen signaling and follows a broadly similar pattern across mammalian species.¹⁰

A signaling molecule called Sonic hedgehog, expressed by the urogenital sinus epithelium, is also required for proper prostate development. Without it, ductal budding fails in animal models.¹¹ By the time a baby boy is born, the gland is present in miniature, sitting in the position it will occupy for life. It stays small through childhood, then undergoes a growth spurt at puberty when testosterone levels rise.

How Its Size Changes Over a Lifetime

The prostate is one of the few organs that keeps growing well into old age. A long-running study following men over time found that the median growth rate was about 0.6 cubic centimeters per year, or roughly a 2.5% annual increase. Around 62% of the men studied showed prostate growth, while about 37% actually had a decrease in size, a less widely known finding.¹² Men whose prostates were already larger (40 cc or more) were about as likely to shrink as to keep growing, while smaller prostates were more prone to continued enlargement.

This growth is driven by the androgen dihydrotestosterone, or DHT, which is converted from testosterone within the prostate itself. DHT plays a helpful role during development but can be the driving force behind pathological enlargement in adulthood.¹³ Drugs that block the conversion of testosterone to DHT can shrink the prostate and relieve urinary symptoms, which makes sense once you understand the hormonal mechanism. DHT is also the main intracellular androgen in the prostate and has been hypothesized to affect the progression of prostate tumors.¹⁴

A young man’s prostate is typically around 20 to 25 cc in volume. By age 60 or 70, it can be double that or more. When the transition zone expands, it can compress the urethra like a fist squeezing a straw. That mechanical compression is the basic reason so many older men develop a weak stream, frequent nighttime urination, and a feeling of incomplete bladder emptying.

Why Its Location Matters for Surgery

The prostate’s position makes it one of the more challenging organs to operate on. It sits deep in the bony pelvis, surrounded by structures whose damage causes life-altering side effects. The neurovascular bundles running along its posterolateral surfaces carry the nerves responsible for erections. The urethral sphincter below it controls urinary continence. Identifying and preserving both during a radical prostatectomy is technically demanding and depends on the surgeon’s detailed understanding of where these structures lie in any given patient, since there is individual variation.¹⁵

Advances in nerve-sparing surgery, particularly with robotic assistance, have improved outcomes precisely because surgeons have developed a more nuanced map of the anatomy around the prostate. Earlier descriptions of the neurovascular bundle treated it as a discrete cable sitting in a predictable spot. More recent dissections have revealed that the nerves are more broadly distributed than previously thought, with connections to the levator ani muscle and rectal wall, making the picture more complex.¹⁶ This diffuse arrangement is part of why some men recover erectile function after surgery and others do not, even when the surgeon attempted a nerve-sparing approach.

Do Women Have a Prostate?

Technically, yes. The Skene’s glands, also called the paraurethral glands, are located on either side of the female urethra and are considered the embryological homolog of the male prostate. They develop from the same urogenital sinus tissue during fetal life and share structural similarities with the male gland. Research in rodents has shown that the female prostate is morphologically similar to the ventral lobe of the male prostate and, when exposed to androgens, grows to resemble it even more closely.¹⁷

This female prostate has been identified in several mammalian species, including humans, rodents, rabbits, bats, and dogs.¹⁸ It produces prostate-specific antigen (PSA), the same marker used in prostate cancer screening for men. Its function in women is not fully understood, though it is sometimes implicated in female ejaculation and can, in rare cases, develop pathology including cysts and even cancer. The gland also undergoes age-related changes, just as the male prostate does.¹⁹

Congenital Variations and Rare Anomalies

Not every prostate develops according to the standard blueprint. One uncommon anomaly is an enlarged prostatic utricle, a small pouch that normally exists as a vestigial remnant of embryonic development at the point where the ejaculatory ducts meet the urethra. When this structure becomes abnormally large, it can act like a cystic mass within or behind the prostate and cause recurrent urinary tract infections, urethral discharge, or urinary retention. In a pooled analysis of reported cases in children, urinary tract infection was the most common presenting complaint (around 41%), and roughly a third of affected patients also had a missing kidney on one side.²⁰ These cases are rare, but they illustrate how even small developmental differences in the prostate’s location and structure can produce real symptoms.

How the Prostate Was Discovered

Given how accessible the prostate is to physical examination, you might assume it was identified early in the history of anatomy. The reality is more tangled. A historical review traced the long and contested path of the prostate’s discovery, noting that ancient physicians including Galen and Herophilus had some awareness of structures in the region, but the gland went without a clear name or description for centuries. Niccolò Massa’s 1536 description is often cited as a milestone, but Massa himself did not claim to be seeing something new and appeared to be reconfirming observations that could be traced back through Avicenna to Galen.²¹ The distinction between the prostate and the seminal vesicles, those paired sacs sitting just behind the bladder, took even longer to sort out. For a long time, anatomists conflated the two, which is understandable given how closely packed these structures are within the pelvis.

That confusion echoes a broader truth about the prostate: its location at the intersection of the urinary and reproductive tracts, tucked deep in the pelvis and surrounded by structures that look somewhat alike, made it one of the harder organs for anatomists to isolate, name, and understand. Even today, imaging the prostate well enough to distinguish benign from malignant changes requires high-resolution MRI and specialized interpretation.²² The gland’s hiddenness has always been both its defining anatomical feature and the main obstacle to understanding it.