| Perineum | |
|---|---|
 The human male perineum (left) and human female perineum (right) | |
 The muscles of the male (left) and female (right) perineum | |
| Details | |
| Pronunciation | /ˌpɛrɪˈniːəm/;[1] |
| System | Musculoskeletal system |
| Artery | Perineal artery,dorsal artery of the penis anddeep artery of the penis |
| Nerve | Perineal nerve,posterior scrotal nerves,dorsal nerve of the penis ordorsal nerve of the clitoris |
| Lymph | Primarilysuperficial inguinal lymph nodes |
| Identifiers | |
| Latin | perineum, perinaeum |
| Greek | περίνεος, περίναιον |
| MeSH | D010502 |
| TA98 | A09.5.00.001 |
| TA2 | 131 |
| FMA | 9579 |
| Anatomical terminology | |
Theperineum (pl.:perineums orperinea) inplacentalmammals is the space between theanus and thegenitals. The human perineum is between the anus andscrotum in the male or between the anus andvulva in the female.[2] The perineum is the region of the body between thepubic symphysis (pubic arch) and thecoccyx (tail bone), including the perineal body and surrounding structures. Theperineal raphe is visible and pronounced to varying degrees.
The perineum is frequently perceived as anerogenous zone, with touch in that area being perceived as both erogenous and aversive by different individuals.[3][4]
The word entered English from late Latin viaGreek περίναιος ~ περίνεοςperinaios, perineos, itself from περίνεος, περίνεοι 'male genitals' and earlier περίςperís 'penis' through influence from πηρίςpērís 'scrotum'. The term was originally understood as a purely male body-part with the perineal raphe seen as a continuation of thescrotal septum sincemasculinization causes the development of a largeanogenital distance in men, in comparison to the corresponding lack of distance in women.[5] As a result offolk etymologies (such as ἰνάω ináō, "to carry off by evacuations"), it is contemporaneously extended to both sexes.
Numerous slang terms for themale perieneum exist, including the "taint" or "gooch" in American slang, as well as the "notcha" in Australian slang.
The perineum is generally defined as thesurface region between thepubic symphysis and thecoccyx. The perineum is below thepelvic diaphragm and between the legs. It is a diamond-shaped area that includes theanus and, in females, thevagina.[6] Its definition varies: it can refer to only the superficial structures in this region or include both superficial and deep structures. The perineum corresponds to theoutlet of the pelvis.
Aline drawn across the surface connecting theischial tuberosities divides the space into two triangles:
The formal anatomical boundaries of the perineum may be said to be:[7]
Theperineal body (orcentral tendon of perineum) is a pyramidal fibromuscular mass in the middle line of the perineum at the junction between theurogenital triangle and theanal triangle. In males, it is found between thebulb of the penis and theanus; in females, it is found between thevagina and anus, and about 1.25 cm (0.49 in) in front of the latter.
The perineal body is essential for the integrity of thepelvic floor, particularly in females. Its rupture during vaginal birth leads to widening of the gap between the anterior free borders oflevator ani muscle of both sides, thus predisposing the child-bearer toprolapse of theuterus,rectum, or even theurinary bladder.Perineal tears andepisiotomy often occur inchildbirth with first-time deliveries, but the risk of these injuries can be reduced by preparing the perineum, often throughmassage.[9]
At this point, the following muscles converge and are attached:
Perinealfascia terminology can be confusing, and there is some controversy over the nomenclature. This stems from the fact that there are two parts to the fascia, the superficial and deep parts, and each of these can be subdivided into superficial and deep parts.
The layers and contents are as follows, from superficial to deep:
| Superficial perineal pouch | Contains superficial perineal muscles:transversus perinei superficialis,bulbospongiosus,ischiocavernosus |
| Inferior fascia ofurogenital diaphragm, orperineal membrane | A membranous layer of thedeep fascia |
| Deep perineal pouch | Contains the deep perineal muscles:transversus perinei profundus,sphincter urethrae membranaceae |
| Superior fascia of the urogenital diaphragm | Considered hypothetical by some modern anatomists, but still commonly used to logically divide the contents of the region |
The perineum region can be considered a distinct area from the pelvic cavity, with the two regions separated by thepelvic diaphragm. The perianal area (peri- andanal) is a subset of the perineum. The following areas are thus classified as parts of the perineal region:
Theanogenital distance is a measure of the distance between the midpoint of the anus and the underside of the scrotum or the vagina. Studies show that the human perineum is twice as long in males as in females.[10] Measuring the anogenital distance in neonatal humans has been suggested as a noninvasive method to determine malefeminisation and thereby predict neonatal and adultreproductive disorders.[11]
Extensive deformation of the pelvic floor occurs during a vaginal delivery. Approximately 85% of women have someperineal tear during a vaginal delivery and in about 69% suturing is required.[12][13][14] Obstetric perineal trauma contributes to postpartum morbidity and frustration of women after delivery. In many women, the childbirth trauma is manifested in advanced age when the compensatory mechanisms of the pelvic floor become weakened, making the problem more serious among the aged population.[15][16]
There are claims that sometimes the perineum is excessively repaired after childbirth, using a so-called "husband stitch" and that this can increase vaginal tightness or result in pain during intercourse.[17]
Perineum sunning is awellness practice that involves exposing the perineum (area between the genitals and anus) to sunlight. Adherents claim various unproven health benefits such as improved libido, circulation, sleep, and longevity.[18] There is no scientific evidence that this behavior promotes any of the alleged benefits.[18] The practice of exposing a sensitive area of skin to sunlight also increases the risk of skin cancers[19] such asmelanoma,squamous cell carcinoma, andbasal-cell carcinoma.[20] Doctors recommend safer alternative options such as relaxation, meditation, and mindfulness, which can also achieve the same desired benefits.[21]
