The informal term “gooch” refers to the perineum, a small but significant region that serves as the floor of the pelvis. The perineum is a universal feature of human anatomy. This complex, diamond-shaped region contains the external openings of the urogenital and digestive tracts. Understanding this region reveals its foundational role in continence, support, and reproductive function.
Defining the Perineum (The Formal Name)
The perineum is the region that corresponds to the outlet of the pelvis, situated inferior to the pelvic diaphragm and between the upper thighs. Its bony boundaries form a distinct diamond shape, connecting the pubic symphysis at the front to the tip of the coccyx at the back. The sides of this diamond are defined by the ischiopubic rami and the ischial tuberosities, often called the “sit bones.”
An imaginary line drawn between the two ischial tuberosities divides the perineal area into two distinct triangles: the anterior urogenital triangle and the posterior anal triangle. The anal triangle contains the anus and the muscles that control it.
The anterior urogenital triangle contains the external urogenital organs and associated structures, including layers of strong fascia and the perineal membrane. A dense, fibromuscular structure called the perineal body is situated at the junction of these two triangles, acting as a central anchor point for several muscles.
Anatomical Differences Between Sexes
Everyone has a perineum, though the contents of the anterior half vary significantly. The posterior section, the anal triangle, is similar across all individuals. The true anatomical differences lie within the urogenital triangle, which accommodates different external genitalia.
In individuals with male anatomy, the urogenital triangle encloses the root of the penis and the scrotum. This region contains the superficial and deep perineal pouches, which house structures like the bulbourethral glands and the external urethral sphincter. The perineal raphe, a seam of tissue visible on the surface, often extends from the anus, across the perineum, and along the underside of the scrotum.
For individuals with female anatomy, the urogenital triangle is adapted to contain the vulva and the vaginal and urethral openings. The deep perineal pouch includes part of the urethra and the vagina. The span of the perineum, particularly the length from the vagina to the anus, is typically shorter in individuals with female anatomy, averaging around 1.5 inches compared to 2 inches or more in individuals with male anatomy.
Function and Clinical Relevance
The perineum provides structural support for the entire pelvic floor, which holds the bladder, rectum, and reproductive organs in place. The perineal body acts as a central hub, where muscle fibers from several different groups converge to strengthen this supportive sling. These attached muscles, such as the bulbospongiosus and the external anal sphincter, are fundamental for controlling bodily functions.
The muscles of the perineum contribute directly to continence, helping to regulate the voluntary passage of urine and feces. The perineum is richly supplied by the pudendal nerve, which transmits sensory information and controls the associated muscles. This neural network makes the region sensitive and involved in sexual arousal and function.
The region is clinically relevant due to its susceptibility to injury, particularly during vaginal childbirth. Perineal tissues must stretch considerably to allow the passage of a baby, which can result in tears or require an episiotomy. Damage to the perineal body during delivery can weaken the pelvic floor, potentially leading to pelvic organ prolapse or issues with urinary or fecal continence later in life.