Anatomical investigation of the pelvic urogenital fascia in 10 formalin-fixed female cadavers: novel insights into the laparoscopic total mesometrial resection.

PURPOSE: Previous anatomical studies of the urogenital fascia (UGF) have focused on males, and there is a lack of relevant anatomical studies on the distribution of the extraperitoneal UGF in females. METHODS: In this investigation, guided by the embryonic development of the female urogenital system, the ventral pelvic fascia structure of 10 female cadavers was dissected, and the distribution and morphology of female extraperitoneal UGF were observed, recorded in text, photographs and video, and 3D modeling was performed. RESULTS: We find that in the female extraperitoneal space there is a migratory fascial structure, the UGF, which surrounds the urogenital system and extends from the perinephric region to the pelvis along with the development of the urogenital organs. The two layers of the UGF are composed of loose connective tissue rich in fat that surrounds the urogenital organs, their accessory vascular structures, and the nerves of the abdominopelvic cavity. In the pelvis, it participates in the formation of the ligamentous structures around the rectum and uterus. Finally, it surrounds the bladder and gradually moves into the loose connective tissue of the medial umbilical fold. CONCLUSIONS: Sorting out the distribution characteristics of UGF has some reference value for studying the metastasis of gynecological tumors, the biomechanical structure of the female pelvis, and the surgical methods of gynecology, colorectal surgery, and hernia surgery.

[The key points to comprehend the pelvic fascia].

Pelvic fascia is considered to be one controversial human anatomic structure. According to the characteristics of specialized surgery, colorectal surgeons, gynecologic surgeons and urologic surgeons respectively marked the pelvic fascia, but the naming is not unified. For some specific anatomic structures (such as pelvic plexus), different scholars have different descriptions of their positions. The lack of standard anatomic terms makes it difficult to understand the corresponding anatomic structures, and also hinders the communication between disciplines. Combined with autopsy research, surgical observation and literature review, we discussed the common puzzles of pelvic clinical anatomy. The main points of this article are as follows. (1) Urogenital fascia and vesicohypogastric fascia are the components of visceral fascia. (2) The visceral fascia and fascia propria of rectum are two separate layers. (3) The pelvic plexus is located on the outside of the confluence of visceral fascia and Denonvilliers' fascia. (4) To understand the pelvic lateral ligament from the perspective of layers. (5) To understand pelvic fascia from a holistic perspective.

A new Hemigrammus from the upper Río Vaupés, Colombia (Characiformes: Characidae), with a discussion on the presence of an enlarged urogenital papilla in the family.

Hemigrammus xaveriellus sp. nov. is described from the upper Río Vaupés basin (Amazon basin), Departamento Guaviare, Colombia. It is distinguished from all congeners by the combination of the following characters: presence of a conspicuous, dark, longitudinal midlateral stripe extending along the body; presence of a conspicuous rounded, horizontally elongated humeral blotch anterior to the beginning of the dark midlateral stripe; seven scale rows between the dorsal fin and lateral line (vs. five to six); and five scale rows between the lateral line and pelvic-fin insertion (vs. three to four). The single mature male of He. xaveriellus possessed a well-developed urogenital papilla, an unusual feature among characids. The presence of an enlarged urogenital papilla in the family is discussed, and comments regarding the putative relationships of the new species are presented.

Do pediatricians routinely perform genitourinary examinations during well-child visits? A review from a large tertiary pediatric hospital.

BACKGROUND: The male genital examination is a common source of discomfort for the patient and medical provider. Performance of male genital examination is imperative; however, as many treatable diagnoses can be made. Undescended testicles (UDTs), hernias, testicular tumors, and urethral abnormalities are all potentially concerning findings which can be discovered on routine examination. OBJECTIVE: The objectives of this study are to determine the rate at which general pediatricians perform routine genitourinary (GU) examinations in the pediatric population and to determine the rate at which UDT are diagnosed or documented in the patient's history. The authors hypothesize the rate of pediatric GU examination during routine well-child visits to be in line with the previously reported rates in the adult literature. STUDY DESIGN: Nine hundred ninety-six consecutive male well-child visits conducted by general pediatricians at the study institution were reviewed. These visits were evaluated for documentation of a detailed GU examination as well as the presence of UDT from these examinations. In addition, past medical and surgical histories were reviewed to determine if a diagnosis of UDT was noted. RESULTS: Pediatricians at the study institution documented GU examinations 99.1% of the time during male well-child visits. Only 1.1% of the cohort had a documentation of UDT at any time point. Of the 11 patients with UDT, 6 boys (54.5%) had spontaneous descent with no referral to urology, whereas 5 (45.5%) required orchidopexy. DISCUSSION: Prior reports suggest 70-75% of routine office visits include a genital examination. None of these reports reviewed the pediatric population, thus making this review novel in this respect. In addition, the results are vastly different from these prior studies as the authors demonstrated over 99% of male well-child examinations included documentation of a thorough genital examination. A limitation of the study is its retrospective nature, which creates a lack of standardization across the data set. In addition, without being physically present in the examination room, one cannot discern whether an examination is simply being documented without actual performance because of the template format of the electronic medical record (EMR). Furthermore, the study was not designed to best evaluate the true rate of UDTs; therefore, the reported rate of 1.1% cannot be accurately associated with a particular age at diagnosis. CONCLUSIONS: Pediatricians do, in fact, document GU examinations on a routine basis. This finding cannot be taken with complete certainty as verification of actual examination performance is impractical. While the data demonstrated a lower than expected rate of UDT, depending upon age at diagnosis, this could indicate that although examinations are being documented, their accuracy may be diminished because of various factors at play in the healthcare system as a whole, including improper exam performance and EMR templates. Follow-up studies are required to verify these potentially changing rates of UDT and to determine if there is discordance between documentation and performance of GU examinations.

Fish sperm biology in relation to urogenital system structure.

Morphology of the urogenital system has evolved during fish speciation. Chondrostei (sturgeons and paddlefishes) possess an excretory system which is called "primitive" in that the sperm ducts enter the kidneys and share the excretory ducts where sperm is mixed with urine before it is released into the spawning environment. Further, in this group of fishes there are also physiological characteristics which are associated with these anatomical features where the mixing of sperm and urine is a prerequisite for the final sperm maturation rather than contamination. In the Holostei (gars and bowfins) which are closely related to the Chondrostei, sperm also naturally mixed with urine, but the physiological role of such mixing for sperm biology has not been described. In contrast, urinary and sperm ducts in the more evolved Teleostei are completely separate, and sperm and urine are not mixed before being released during spawning. Thus, urine constitutes an inappropriate environment which can be a source of problems when sperm is collected during fisheries practices. In this review, the consequences of such divergent conditions in the urogenital anatomy will be considered in relation to general features of fish sperm biology and in relation to aquaculture and fisheries practices.

Deep learning enables automatic quantitative assessment of puborectalis muscle and urogenital hiatus in plane of minimal hiatal dimensions.

OBJECTIVES: To measure the length, width and area of the urogenital hiatus (UH), and the length and mean echogenicity (MEP) of the puborectalis muscle (PRM), automatically and observer-independently, in the plane of minimal hiatal dimensions on transperineal ultrasound (TPUS) images, by automatic segmentation of the UH and the PRM using deep learning. METHODS: In 1318 three- and four-dimensional (3D/4D) TPUS volume datasets from 253 nulliparae at 12 and 36 weeks' gestation, two-dimensional (2D) images in the plane of minimal hiatal dimensions with the PRM at rest, on maximum contraction and on maximum Valsalva maneuver, were obtained manually and the UH and PRM were segmented manually. In total, 713 of the images were used to train a convolutional neural network (CNN) to segment automatically the UH and PRM in the plane of minimal hiatal dimensions. In the remainder of the dataset (test set 1 (TS1); 601 images, four having been excluded), the performance of the CNN was evaluated by comparing automatic and manual segmentations. The performance of the CNN was also tested on 117 images from an independent dataset (test set 2 (TS2); two images having been excluded) from 40 nulliparae at 12 weeks' gestation, which were acquired and segmented manually by a different observer. The success of automatic segmentation was assessed visually. Based on the CNN segmentations, the following clinically relevant parameters were measured: the length, width and area of the UH, the length of the PRM and MEP. The overlap (Dice similarity index (DSI)) and surface distance (mean absolute distance (MAD) and Hausdorff distance (HDD)) between manual and CNN segmentations were measured to investigate their similarity. For the measured clinically relevant parameters, the intraclass correlation coefficients (ICCs) between manual and CNN results were determined. RESULTS: Fully automatic CNN segmentation was successful in 99.0% and 93.2% of images in TS1 and TS2, respectively. DSI, MAD and HDD showed good overlap and distance between manual and CNN segmentations in both test sets. This was reflected in the respective ICC values in TS1 and TS2 for the length (0.96 and 0.95), width (0.77 and 0.87) and area (0.96 and 0.91) of the UH, the length of the PRM (0.87 and 0.73) and MEP (0.95 and 0.97), which showed good to very good agreement. CONCLUSION: Deep learning can be used to segment automatically and reliably the PRM and UH on 2D ultrasound images of the nulliparous pelvic floor in the plane of minimal hiatal dimensions. These segmentations can be used to measure reliably UH dimensions as well as PRM length and MEP. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Role of Androgens in Female Genitourinary Tissue Structure and Function: Implications in the Genitourinary Syndrome of Menopause.

INTRODUCTION: Genitourinary conditions in women increase in prevalence with age. Androgens are prerequisite hormones of estrogen biosynthesis, are produced in larger amounts than estrogens in women, and decrease throughout adulthood. However, research and treatment for genitourinary complaints have traditionally focused on estrogens to the exclusion of other potential hormonal influences. AIM: To summarize and evaluate the evidence that androgens are important for maintaining genitourinary health in women and that lack of androgenic activity can contribute to the development of symptoms of the genitourinary syndrome of menopause. METHODS: The role of androgens in the pathophysiology, diagnosis, and treatment of genitourinary syndrome of menopause was discussed by an international and multidisciplinary panel during a consensus conference organized by the International Society for the Study of Women's Sexual Health. A subgroup further examined publications from the PubMed database, giving preference to clinical studies or to basic science studies in human tissues. MAIN OUTCOME MEASURES: Expert opinion evaluating trophic and functional effects of androgens, their differences from estrogenic effects, and regulation of androgen and estrogen receptor expression in female genitourinary tissues. RESULTS: Androgen receptors have been detected throughout the genitourinary system using immunohistochemical, western blot, ligand binding, and gene expression analyses. Lower circulating testosterone and estradiol concentrations and various genitourinary conditions have been associated with differential expression of androgen and estrogen receptors. Supplementation of androgen and/or estrogen in postmenopausal women (local administration) or in ovariectomized animals (systemic administration) induces tissue-specific responses that include changes in androgen and estrogen receptor expression, cell growth, mucin production, collagen turnover, increased perfusion, and neurotransmitter synthesis. CONCLUSION: Androgens contribute to the maintenance of genitourinary tissue structure and function. The effects of androgens can be distinct from those of estrogens or can complement estrogenic action. Androgen-mediated processes might be involved in the full or partial resolution of genitourinary syndrome of menopause symptoms in women. Traish AM, Vignozzi L, Simon JA, et al. Role of Androgens in Female Genitourinary Tissue Structure and Function: Implications in the Genitourinary Syndrome of Menopause. Sex Med Rev 2018;6:558-571.

Regional morphology and mucus composition in the urogenital papilla skin of the blackbelly rosefish Helicolenus dactylopterus (Delaroche, 1809).

Blackbelly rosefish Helicolenus dactylopterus is a zygoparous fish whose males are equipped with the copulating organ named urogenital papilla (UP). This study deals with the morphology and the glycoconjugate pattern of the UP epidermis, which is the male tissue interacting with the female internal body during copulation. The carbohydrate content was studied by means of conventional and lectin histochemistry. The epidermis was shown to be a stratified cuboidal epithelium and to exhibit characteristic intraepithelial pits in the apical zone. The mucous cells are scattered in the epidermis. The epidermal cell layers and their thickness as well as the size of mucous cells varied along the UP. Conventional histochemistry showed that the mucous cells contained i) only neutral glycoproteins in the basal zone; ii) both neutral and acidic non-sulphated glycans as well as only acidic non-sulphated or sulphated glycoconjugates in the intermediate zone; iii) neutral and sulphated glycoconjugates in the apical zone. The mucous cells in the basal region expressed O-linked (mucin type) glycans terminating with αGalNAc, Galß1,3GalNAc which could be α2,3-linked to sialic acid, and high mannose type N-linked glycans terminating with fucose, lactosamine, and sialic α2,6-linked to galactose/N-acetylgalactosamine; terminal Gal and terminal/internal GlcNAc were also found. The mucous cells in the intermediate zone lacked Galß1,3GalNAc and showed less terminal α2,3-linked sialic acid, lactosamine, fucose, galactose, and internal N-acetylglucosamine residues. In the apical region, mucous cells only exhibited O-glycans terminating with GalNAc and N-acetylglucosamine. The demonstrated region-specific differences in the UP skin provide new insights into the reproductive biology of fishes with internal fertilization.

Comparative anatomy on 3-D MRI of the urogenital sinus and the periurethral area before and during the second stage of labor during childbirth.

PURPOSE OF THE STUDY: To describe the observable MRI changes in the urogenital sinus during the second stage of labor and delivery by comparing the changes in the positions of the anatomical structures of the maternal perineum using MRI-based vector 3-D models. MATERIALS AND METHODS: Seven pregnant women underwent 3-D MRI sequences using a Philips 1 T Panorama open MRI during the pre-labor period and during the second stage of labor. A 3-D vector reconstruction platform (BABYPROGRESS, France) enabled the transformation of volumes of 2-D images into finite element meshes. The polygonal meshes labeled with the principal components of the urogenital sinus were used as part of a biomechanical study of the pressure exerted on the perineum during fetal descent. RESULTS: The expansion of the urogenital sinus was observed in all patients. Qualitative stretching was observed toward the rear and bottom of the iliococcygeus, pubococcygeus, puborectalis and obturator internus muscles. Significant length differences were measured along the iliococcygeus and pubococcygeus muscles but not along the tendinous arch of the levator ani or the puborectalis muscle. The inversion of the levator ani muscle curvature was accompanied by the transmission of pressure generated during fetal descent to the pubic muscle insertions and the descent of the tendinous arch of the levator ani. CONCLUSION: Mechanical pressures responsible for the tensioning of the constituent muscles of the urogenital sinus were qualitatively identified during the second stage of labor. MRI-based vector 3-D models allow the quantitative assessment of levator ani muscle stretching during labor, but 2-D MRI is not sufficient for describing perineal expansion. Vector 3-D models from larger scale studies have the potential to aid in the calibration of a realistic simulation based on the consideration of the reaction of each muscular element. These models offer perspectives to enhance our knowledge regarding perineal expansion during childbirth as a risk factor for postpartum perineal defects.

Histology of the Urogenital System in the American Bullfrog (Rana catesbeiana), with Emphasis on Male Reproductive Morphology.

Previous studies have revealed variations in the urogenital system morphology of amphibians. Recently, the urogenital system of salamanders was reviewed and terminology was synonymized across taxa. Discrepancies exist in the terminology describing the urogenital system of anurans, which prompted our group to develop a complete, detailed description of the urogenital system in an anuran species and provide nomenclature that is synonymous with those of other amphibian taxa. In Rana catesbeiana, sperm mature within spermatocysts of the seminiferous tubule epithelia and are transported to a series of intratesticular ducts that exit the testes and merge to form vasa efferentia. Vasa efferentia converge into single longitudinal ducts (Bidder's ducts) on the lateral aspects of the kidneys. Branches from the longitudinal ducts merge with genital kidney renal tubules through renal corpuscles. The nephrons travel caudally and empty into the Wöffian ducts. Similar to salamanders, the caudal portion of the kidneys (termed the pelvic kidneys in salamanders) only possesses nephrons involved in urine formation, not sperm transport. Data from the present study provide a detailed description and synonymous nomenclature that can be used to make future comparative analyses between taxa more efficient.

Comparative morphology of the reproductive system of seven species of ostariophysan fishes from the upper Das Velhas River, Brazil.

The success of fishes in different environments is related with the variation of reproductive strategies developed by the systematic group, which is reflected in the morphology of the reproductive system and can have ecological and evolutionary implications. This study comparatively analyzed the morphological characteristics of the male and female reproductive systems of ostariophysan fish species from the upper Das Velhas River in the São Francisco River basin, Brazil. In order to accomplish this, 393 specimens belonging to seven fish species were sampled between April 2010 and June 2015 for histological, ultrastructural, histochemical, and morphometric analyses. All the species examined have anastomosing tubular testes with unrestricted distribution of spermatogonia. Astyanax bimaculatus, A. fasciatus, A. scabripinnis, and Harttia torrenticola had their spermatozoa embedded in a glycoprotein secretion within the tubule lumen. Most species had type I spermiogenesis, whereas Rhamdia quelen had type III spermiogenesis. While all females examined had asynchronous oocyte development, there were remarkable morphological, histochemical, and morphometric differences in the ovarian follicles and enveloping layers. Hoplias malabaricus and H. torrenticola, which exhibit parental care behaviour, had a significantly larger diameter of vitellogenic oocytes and larger spermatozoa nuclei. Apareiodon ibitiensis, H. torrenticola, and A. scabripinnis, species that have rheophilic preferences, exhibited a thicker zona radiata than the other species examined. The follicular cells of R. quelen and H. torrenticola were columnar and produced a jelly coat and mucosubstances, respectively. The females of the seven fish species studied show a correlation of the reproductive strategies with the reproductive system morphology, while males retained more similar morphological characteristics between species. J. Morphol. 278:170-181, 2017. © 2016 Wiley Periodicals,Inc.

Topographic Anatomy and its development in Urology in the 20th Century. The work of Salvador Gil Vernet

Salvador Gil Vernet was a mid-twentieth-century Spanish anatomist and urologist who made highly significant advances in the field of urological anatomy with his studies on the topographic anatomy of the male pelvis and perineum. He was the first author in the twentieth century to precisely and accurately describe the anatomy of the external urethral sphincter, detrusor, posterior urethra and prostato-urethral musculature. In addition, his contributions to pelvic plexus neuroanatomy, with the description of the cavernous nerves and autonomic innervation of the external urethral sphincter, were used to develop a modern and less invasive surgical technique for treating urogenital disease. His research on the embryology and topographical anatomy of the prostate gland also helped him to define the first regional anatomical model of the prostate, which would act as the cornerstone for the development of current zonal anatomy. In this paper we present a summary of his most important discoveries, which have led him to be considered one of the pioneers of urological anatomy of the previous century

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Morphostructural analysis of the male reproductive system and DNA barcoding in Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae).

Balclutha brevis Lindberg 1954 is an allochthonous leafhopper infesting an invasive grass, Pennisetum setaceum, in Sicily and in mainland Europe; therefore, this species could compete with populations of native species, thus contributing to the loss of biodiversity. Considering the ecological implications of B. brevis, investigations on all its biological aspects represent, therefore, a premise for further studies in applied sciences. Based on the lacking ultrastructural data about the reproductive systems of the Auchenorrhyncha, we carried out morphostructural investigations on the male reproductive system of B. brevis. Further, a first report of DNA barcoding analysis (amplification and sequencing of Cytochrome Oxidase I gene) has also been performed to characterize B. brevis compared to other congeneric species. From a morphological point of view, the male reproductive system of B. brevis has an organization comparable to the general anatomical features of most of the Auchenorrhyncha species; however, comparing our data with those concerning the different groups of Cicadomorpha, some considerations are discussed. As for the histological and ultrastructural investigations, our results show a secretory activity of the various examined structures, mainly in the lateral ejaculatory ducts and in the accessory glands. The latter, in particular, show morphostructural differences comparing the distal tract to the proximal one; moreover, the histochemical techniques showed the possible presence of a lipid component in the peculiar cytoplasmic granules found in the gland cells. The significance of these findings in the accessory glands is discussed. Finally, the ultrastructural features found in the seminal vesicles are different from those of the lateral ejaculatory ducts and are indicative of the different roles played by these structures in the organization of the spermatozoa bundles.

An illustrated anatomical ontology of the developing mouse lower urogenital tract.

Malformation of the urogenital tract represents a considerable paediatric burden, with many defects affecting the lower urinary tract (LUT), genital tubercle and associated structures. Understanding the molecular basis of such defects frequently draws on murine models. However, human anatomical terms do not always superimpose on the mouse, and the lack of accurate and standardised nomenclature is hampering the utility of such animal models. We previously developed an anatomical ontology for the murine urogenital system. Here, we present a comprehensive update of this ontology pertaining to mouse LUT, genital tubercle and associated reproductive structures (E10.5 to adult). Ontology changes were based on recently published insights into the cellular and gross anatomy of these structures, and on new analyses of epithelial cell types present in the pelvic urethra and regions of the bladder. Ontology changes include new structures, tissue layers and cell types within the LUT, external genitalia and lower reproductive structures. Representative illustrations, detailed text descriptions and molecular markers that selectively label muscle, nerves/ganglia and epithelia of the lower urogenital system are also presented. The revised ontology will be an important tool for researchers studying urogenital development/malformation in mouse models and will improve our capacity to appropriately interpret these with respect to the human situation.

Retrograde positive contrast urethrocystography of the fish urogenital system.

The radiological differences between the urinary tract of Dicentrarchus labrax, Sparus aurata, Tinca tinca, and Cyprinus carpio are shown. In fresh water teleosts the urinary bladder is sigmoid and a short urethra leads to the urinary pore. Genital and anal pores are present. In Sparus aurata the urinary bladder has a globoid shape. In Dicentrarchus labrax the urinary bladder is smaller and elongate. In both marine teleosts a single urogenital pore is visible. Positive contrast was used to survey the urogenital system and evaluate shape and size of the bladder, urethra, ureter, and gonadal ducts. Results demonstrate the morphological variability of the urinary bladder and the craniodorsal entry of the ureters into the bladder. It is envisaged that this work will provide baseline information for further imaging studies for investigating the urogenital morphology and can be applied to identify disorders in fishes. Furthermore, the main interest of this study is that it demonstrates the morphological variability of the lower urinary system that exists between different species of fishes.

Renal development: a complex process dependent on inductive interaction.

Renal development begins in-utero and continues throughout childhood. Almost one-third of all developmental anomalies include structural or functional abnormalities of the urinary tract. There are three main phases of in-utero renal development: Pronephros, Mesonephros and Metanephros. Within three weeks of gestation, paired pronephri appear. A series of tubules called nephrotomes fuse with the pronephric duct. The pronephros elongates and induces the nearby mesoderm, forming the mesonephric (Woffian) duct. The metanephros is the precursor of the mature kidney that originates from the ureteric bud and the metanephric mesoderm (blastema) by 5 weeks of gestation. The interaction between these two components is a reciprocal process, resulting in the formation of a mature kidney. The ureteric bud forms the major and minor calyces, and the collecting tubules while the metanephrogenic blastema develops into the renal tubules and glomeruli. In humans, all of the nephrons are formed by 32 to 36 weeks of gestation. Simultaneously, the lower urinary tract develops from the vesico urethral canal, ureteric bud and mesonephric duct. In utero, ureters deliver urine from the kidney to the bladder, thereby creating amniotic fluid. Transcription factors, extracellular matrix glycoproteins, signaling molecules and receptors are the key players in normal renal development. Many medications (e.g., aminoglycosides, cyclooxygenase inhibitors, substances that affect the renin-angiotensin aldosterone system) also impact renal development by altering the expression of growth factors, matrix regulators or receptors. Thus, tight regulation and coordinated processes are crucial for normal renal development.

[Design of a multifunctional and transparent urinary system model].

This article describes a novel Multifunctional and Transparent Urinary System Model (MTUSM), which can be applied to anatomy teaching, operational training of clinical skills as well as simulated experiments in vitro. This model covers kidneys, ureters, bladder, prostate, male and female urethra, bracket and pedestal, etc. Based on human anatomy structure and parameters, MTUSM consists of two transparent layers i. e. transparent organic glass external layer, which constraints the internal layer and maintains shape of the model, and transparent silica gel internal layer, which possesses perfect elasticity and deformability. It is obvious that this model is preferable in simulating the structure of human urinary system by applying hierarchical fabrication. Meanwhile, the transparent design, which makes the inner structure, internal operations and experiments visual, facilitates teaching instruction and understanding. With the advantages of simple making, high-findelity, unique structure and multiple functions, this model will have a broad application prospect and great practical value.

The urogenital-hypogastric sheath: an anatomical observation on the relationship between the inferomedial extension of renal fascia and the hypogastric nerves.

PURPOSE: The study aimed to perform an anatomical observation on the inferomedial extension of the renal fascia (RF) to the pelvis and explore its relationship with the hypogastric nerves (HGNs). METHODS: Gross anatomy was performed on 12 formalin-fixed and 12 fresh cadavers. Sectional anatomy was performed on four formalin-fixed cadavers. RESULTS: Different from the traditional concept, both the anterior and posterior RF included the outer and inner layer with different inferomedial extensions. The multiple layers of RF extended downward to form a sandwich-like and compound fascia sheath with potential and expandable spaces which was named as "the urogenital-hypogastric sheath." Below the level of the origin of the inferior mesenteric artery, the bilateral urogenital-hypogastric sheath communicated with the counterpart in front of the great vessels in the midline and the superior hypogastric plexus ran into the urogenital-hypogastric sheath which carried the HGNs, ureters, and genital vessels downward to their terminations in the pelvis. In the retrorectal space, the urogenital-hypogastric sheath surrounded the fascia propria of the rectum posterolaterally as a layer of coat containing HGNs. CONCLUSION: The multiple layers of RF with different extensions are the anatomical basis of the formation of the urogenital-hypogastric sheath. As a special fascial structure in the retroperitoneal space and the pelvis, emphasis on its formation and morphology may be helpful for not only unifying the controversies about the relationship between the pelvic fascia and HGNs but also improving the intraoperative preservation of the HGNs by dissecting in the correct surgical plane.