Neurovascular anatomy of the developing human fetal penis and clitoris.

The human penile and clitoral development begins from a morphologically indifferent genital tubercle. Under the influence of androgen, the genital tubercle forms the penis by forming a tubular urethra within the penile shaft. Without the effect of the androgen, the genital tubercle differentiates into the clitoris, and a lack of formation of the urethra within the clitoris is observed. Even though there are similarities during the development of the glans penis and glans clitoris, the complex canalization occurring along the penile shaft eventually leads to a morphological difference between the penis and clitoris. Based on the morphological differences, the main goal of this study was to define the vascular and neuronal anatomy of the developing penis and clitoris between 8 and 12 weeks of gestation using laser scanning confocal microscopy. Our results demonstrated there is a co-expression of CD31, which is an endothelial cell marker, and PGP9.5, which is a neuronal marker in the penis where the fusion is actively occurring at the ventral shaft. We also identified a unique anatomical structure for the first time, the clitoral ridge, which is a fetal structure running along the clitoral shaft in the vestibular groove. Contrary to previous anatomical findings which indicate that the neurovascular distribution in the developing penis and clitoris is similar, in this study, laser scanning confocal microscopy enabled us to demonstrate finer differences in the neurovascular anatomy between the penis and clitoris.

Somatic and autonomic nerve density and distribution within the clitoris: an immunohistochemical study in adult female cadavers.

INTRODUCTION AND HYPOTHESIS: Knowledge of clitoral neuroanatomy is critical to vulvar surgery. We sought to characterize the density and distribution of autonomic and somatic nerves supplying the clitoris. METHODS: Pelvic tissue harvested from female cadavers was sectioned axially at three anatomic levels: the proximal aspect of the clitoral body (CB), the distal CB, and the glans. The CB, glans, and the surrounding connective tissue (dorsal, lateral, and ventral) were outlined microscopically. An area containing large nerve bundles dorsal to the CB, referred to as the dorsal nerve subregion, was analyzed separately. Double-immunofluorescent staining for beta III tubulin (ßIIIT), a global axonal marker, and myelin basic protein (MBP), a myelinated nerve marker, was performed. Threshold-based automatic image-segmentation distinguished stained areas. Autonomic and somatic density were calculated as percentage of tissue stained with ßIIIT alone, and ßIIIT and MBP respectively. Comparisons were made using nonparametric Friedman tests. RESULTS: Seven cadavers, aged 22-81, were examined. Somatic (mean 4.42%, SD ± 1.97) and autonomic (2.14% ± 2.42) nerve density was highest in the dorsal nerve subregion and dorsal region at the distal CB level. Compared with the CB, somatic density was higher in proximal (0.05% ± 0.03 vs 1.27% ± 0.69, p = 0.03) and distal (0.29% ± 0.25 vs 1.09% ± 0.41, p = 0.05) dorsal regions. Somatic density was greater in the glans than in the surrounding lateral (0.78% ± 0.47 vs 0.43% ± 0.23, p = 0.03) and ventral (0.78% ± 0.47 vs 0.52% ± 0.2, p = 0.03) regions. Autonomic density was greater than somatic in all areas, except for the dorsal nerve subregion. CONCLUSIONS: Somatic and autonomic nerve density were greatest in a well-defined region dorsal to the CB. Surgical preservation of this region is critical for maintaining nerve supply to the clitoris.

Developmental and sexual dimorphic atlas of the prenatal mouse external genitalia at the single-cell level.

Birth defects of the external genitalia are among the most common in the world. Proper formation of the external genitalia requires a highly orchestrated process that involves special cell populations and sexually dimorphic hormone signaling. It is clear what the end result of the sexually dimorphic development is (a penis in the male versus clitoris in the female); however, the cell populations involved in the process remain poorly defined. Here, we used single-cell messenger RNA sequencing in mouse embryos to uncover the dynamic changes in cell populations in the external genitalia during the critical morphogenetic window. We found that overall, male and female external genitalia are largely composed of the same core cellular components. At the bipotential stage of development (embryonic day or E14.5), few differences in cell populational composition exist between male and female. Although similar in cell population composition, genetic differences in key sexual differentiation developmental pathways arise between males and females by the early (E16.5) and late (E18.5) differentiation stages. These differences include discrete cell populations with distinct responsiveness to androgen and estrogen. By late sexual differentiation (E18.5), unique cell populations in both male and female genitalia become apparent and are enriched with androgen- and estrogen-responsive genes, respectively. These data provide insights into the morphogenesis of the external genitalia that could be used to understand diseases associated with defects in the external genitalia.

How well do we truly understand clitoral anatomy? An Irish maternity hospital's perspective.

BACKGROUND: The clitoris has long been ignored in medical literature and teaching, with the first paper describing its anatomy only published in 1993. It is essential that those working in women's health understand the anatomy of this important female sexual organ. AIMS: The aim of this study was to assess the level of knowledge of the anatomy of the clitoris across five cohorts in a busy teaching maternity hospital in Ireland. MATERIALS AND METHODS: A questionnaire was devised, asking ten consultants, ten non-consultant hospital doctors (NCHDs), ten midwives, ten midwifery students and ten medical students to name the anatomical parts of a 3D model of the clitoris. RESULTS: None of the 50 respondents could name all five labelled parts of the clitoris, and 38 of respondents could not correctly name one anatomical part. CONCLUSIONS: It is evident that there is a lack of knowledge of the anatomical parts of the clitoris among the medical staff included in this study. This reflects a lack of adequate teaching in this area in both past and recent years. Despite this, we acknowledge that women's health and sexual health awareness is improving all of the time, and we hope that this study can highlight the need for reformed teaching in this area.

Beyond the tip of the iceberg: A meta-analysis of the anatomy of the clitoris.

An understanding of ranges in clitoral anatomy is important for clinicians caring for patients including those who have had female genital mutilation, women seeking genital cosmetic surgery, or trans women seeking reconstructive surgery. The aim of this meta-analysis is to investigate the ranges in clitoral measurements within the literature. A meta-analysis was performed on Ovid Medline and Embase databases following the PRISMA protocol. Measurements of clitoral structures from magnetic imaging resonance, ultrasound, cadaveric, and living women were extracted and analyzed. Twenty-one studies met the inclusion criteria. The range in addition to the average length and width of the glans (6.40 mm; 5.14 mm), body (25.46 mm; 9.00 mm), crura (52.41 mm; 8.71 mm), bulb (52.00 mm; 10.33 mm), and prepuce (23.19 mm) was calculated. Furthermore, the range and average distance from the clitoris to the external urethral meatus (22.27 mm), vagina (43.14 mm), and anus (76.30 mm) was documented. All erectile and non-erectile structures of the clitoris present with substantial range. It is imperative to expand the literature on clitoral measurements and disseminate the new results to healthcare professionals and the public to reduce the sense of inadequacy and the chances of iatrogenic damage during surgery.

Hoodplasty: Individualized Approach for Labiaplasties.

INTRODUCTION: Hoodplasties and labia minora reductions are some of the most requested operative procedures by women distressed with the appearance of their vulvar region. In the majority of cases, a concomitant hoodplasty (HP) is performed to achieve a better aesthetic appearance. Various surgical methods have been described for the removal of excess tissue within the clitoris hood area. MATERIALS AND METHOD: This study aims to describe a single surgeon's preference and results in her private practise in 630 patients who underwent labiaplasty mainly because of dissatisfaction with the aesthetic appearance. RESULTS: Of the 630 labiaplasties performed, 303 had clitoris hood excess, 44% of cases with concomitant HP and in 7.9% of cases only a HP was performed. The study was done between September 2009 and December 2021 and the HP technique was longitudinal excision in 97% of patients and horseshoe excision in 4.95% of them. Surgeries lasted between 30 and 60 min. 98% of the patients claimed an improvement in self-esteem and 96% claimed improvement in sex life post-surgery. No major complications occurred. DISCUSSION: An isolated labiaplasty technique in patients with hood excess results in disharmony in the area. HP can be considered as a subdivision of a labioplasty. Extended central wedge labia minora resection (V-plasty) is a commonly used procedure in LP operations but can limit the excess clitoris hood resection. Edge labia minora resection can easily be combined with longitudinal excision of the clitoral hood, and when also horizontal clitoris hood excess is present can also be addressed by converting the resection from longitudinal into a horse hose resection. Limitations in the study include lack of use of validated assessments for the satisfaction of aesthetic outcomes and that all the procedures were performed by a single senior surgeon, which can be seen as a strength but also a limitation because of the high risk of bias. Moreover, there was no comparative cohort for the study population. Furthermore, we could not find comparative cohorts in previously reported techniques in the literature either. CONCLUSION: Clitoris hood resections should be treated on an individualized approach and adapted according to the excess present. It is important when a patient requests a labiaplasty to always address the clitoris hood during the consultation to avoid unsatisfied patients afterwards. Many patients come just focussed on their labia minora excess and when corrected, realize the clitoris hood excess was also part of the problem. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 .

Axonal and Glial PIEZO1 and PIEZO2 Immunoreactivity in Human Clitoral Krause's Corpuscles.

Krause's corpuscles are typical of cutaneous mucous epithelia, like the lip vermillion or the glans clitoridis, and are associated with rapidly adapting low-threshold mechanoreceptors involved in gentle touch or vibration. PIEZO1 and PIEZO2 are transmembrane mechano-gated proteins that form a part of the cationic ion channels required for mechanosensitivity in mammalian cells. They are involved in somatosensitivity, especially in the different qualities of touch, but also in pain and proprioception. In the present study, immunohistochemistry and immunofluorescence were used to analyze the occurrence and cellular location of PIEZO1 and PIEZO2 in human clitoral Krause's corpuscles. Both PIEZO1 and PIEZO2 were detected in Krause's corpuscles in both the axon and the terminal glial cells. The presence of PIEZOs in the terminal glial cells of Kraus's corpuscles is reported here for the first time. Based on the distribution of PIEZO1 and PIEZO2, it may be assumed they could be involved in mechanical stimuli, sexual behavior, and sexual pleasure.

Female orgasm, reproduction and couple relationships.

A deficit or problematic achievement of female orgasm is often classified as a sexual disorder that creates complications in the sex life of couples. This assumption is generally accepted, even though vaginal anorgasmia is an accepted statistical norm and non-coital methods of generating female orgasm are not as easy as they are for men. Female orgasms manifest themselves in different ways; they are variable and can be dependent on a number of variable factors. Some theories suggest a high degree of correlation between the capacity for orgasmic experience, sexual attitudes and behaviour, but also with reproductive potential or the stability of the given couple's relationship. Female orgasm is often seen as a discriminatory mechanism influencing attitudes towards sexuality or even as a kind of fertility catalyst. There is no consensus on the importance of female orgasm. The results of some relevant studies refute theories about the female orgasm's positive influence on adaptive functions of the couple's relationship, as well as its influence on fertility. The orgasm in women is most likely an evolutionary by-product of its male variant, since the clitoris and penis have an identical embryonic basis of development. Female anorgasmia should not be considered an unquestioned diagnosis, let alone a psychiatric construct leading to a paradigm in which anorgasmia is categorically the cause of frustration or other problems.

Stereological comparison of smooth muscle, collagen, and elastic fibers of the clitoris and glans penis in young adults.

OBJECTIVE: To compare the collagen, elastic fibers, and smooth muscle content of the clitoris and the glans penis in young adults. MATERIALS AND METHODS: The clitoris and the glans penis of six women and six men (mean age 25±3) who died as a result of accidents were excised. The samples were placed under a formaldehyde solution and histologically processed. Masson's trichrome and Weigert's resorcin-fuchsin stain was used to highlight the elastic fibers, smooth muscle, and collagen. Stereological analysis was conducted in 5 random fields of 5 slides for each sample. For statistical analysis, the unpaired t-test was used to compare values between groups, and a value of P<0.05 was considered as significant for all analyses. RESULTS: Stereology revealed a mean smooth muscle content of 35.84±6.46% and 31.64±4.74% for the clitoris and glans penis, respectively, while it also revealed collagen content of 26.11±7.41% and 28.44±3.55% and elastic fibers content of 24.12±4.34% and 30.97±6.13% for the clitoris and glans penis, respectively. The statistical analysis showed no significant differences between them. CONCLUSION: Regardless of anatomical differences, the volumetric density of collagen, elastic fibers, and smooth muscle were similar for the clitoris and glans penis in young adults, a feature possibly explained by their embryology.

Anatomic relationships of the clitoral body, bulbs of the vestibule, and urethra.

BACKGROUND: Although recent studies have enhanced our understanding of the anatomy of the clitoris and its somatic innervation, less emphasis has been placed on the anatomic relationships of the clitoris to its surrounding structures. OBJECTIVE: This study aimed to further characterize the gross and histologic relationships of the clitoris, vestibular bulbs, and urethra. STUDY DESIGN: Detailed dissections were performed in 30 unembalmed female cadavers. In 23 specimens, gross dissections were performed, and relationships of the clitoris, vestibular bulbs, and urethra were annotated. Histologic evaluation was performed in 7 specimens, in which tissues were harvested within 24 hours from death. Descriptive statistics were used for data analyses. RESULTS: The clitoral body consisted of 2 components, the proximal body and the distal body. The distal body was oriented ≤90° from the proximal body, forming an outer and inner angle at the inflection point. A "septumlike" arrangement of fibroconnective and vascular tissues was noted between the inner angle of the clitoral body and the urethra. Neurovascular bundles coursed laterally along the clitoral body and the surfaces of the crura and vestibular bulbs. The vestibular bulbs approached each other over the ventral surface of the urethra, at the commissure of the vestibular bulbs. Each bulb was separated by fibrous tissue and did not merge along the midline. The vestibular bulbs approximated the clitoral body, but the erectile tissue of the vestibular bulbs was separated from the corpora cavernosa of the clitoral body by the tunica albuginea. The erectile tissue of the vestibular bulbs abutted the ventrolateral walls of the urethra but was separated from the urethral mucosa by an indiscrete layer of erectilelike tissue with dense stroma. CONCLUSION: This study provided gross and histological confirmation of the relationships of the clitoris, vestibular bulbs, and urethra. Detailed knowledge of the anatomy of the clitoris is crucial for reducing surgical complications associated with periclitoral and distal urethral procedures, which may adversely affect sexual arousal and sexual function.

How many nerve fibers innervate the human glans clitoris: a histomorphometric evaluation of the dorsal nerve of the clitoris.

INTRODUCTION: It is frequently quoted in mainstream media that the clitoris has "8000 nerve endings." However, no study has yet quantified the number of nerve fibers (axons) innervating the human clitoris. The dorsal nerves of the clitoris (DNCs) are the primary source of sensation and somatic clitoral innervation. Therefore, reporting the number of axons in the DNCs is an important step in our understanding of clitoral innervation and sexual response with implications for many fields of medical practice. The purpose of this study is to quantify the mean number of axons in the human DNCs and to report the approximate mean number of nerve fibers that innervate the human glans clitoris. METHODS: DNC samples were obtained from 7 transmasculine patients undergoing gender-affirming phalloplasty surgery. At the time of nerve coaptation, a small excess of the DNC (5 mm) was collected for analysis at the proximal level of the clitoral body, just distal of the emergence of the DNCs from underneath the pubic symphysis. Samples were placed into 3% glutaraldehyde fixative, postfixed in 1% osmium tetroxide, and serially dehydrated in ethanol and toluene. Samples were then embedded in araldite, sectioned on an ultramicrotome into 1-µm cross sections, and counterstained with 1% toluidine blue. Histomorphometric evaluation was performed at 1000x magnification with a Leitz Laborlux S microscope and image analysis software (Clemex Vision Professional) to obtain an axon counts. Descriptive statistics were performed to yield a mean and standard deviation of the number of axons in the DNCs. Assuming anatomic symmetry between bilateral DNCs, mean total number of somatic nerve fibers innervating the human glans clitoris was obtained by doubling the mean count of the DNCs. RESULTS: Seven sample DNCs were collected. Of those, 5 were analyzed as 2 did not have sufficient nerve tissue present. The mean number of nerve fibers in the human DNCs was 5140 (SD = 218.4). The mean number of myelinated nerve fibers innervating the human clitoris was 10,281 (SD = 436.8). CONCLUSION: This study is the first to report the number of axons in the human DNC, at a mean 5140. Given the bilateral nature of clitoral innervation and symmetry of anatomic structures, the approximate mean number of myelinated axons that innervate the human glans clitoris is 10,280. When the uncaptured unmyelinated fibers and contributions from the cavernosal innervation are accounted for, it is clear that far Moree than 8000 axons innervate the human clitoris.

Minimally Invasive Two-passage Electrical Genital Nerve Stimulation: A Human Cadaver Study of a New Technique.

STUDY OBJECTIVE: To present and evaluate the feasibility of a new technique of lead-electrode stimulation to the genital nerves using a 2-step, double-passage retropubic/retrograde approach. DESIGN: Prospective observational study. INTERVENTIONS: The procedure was initiated in the retropubic passage by placing the electrode from below through a paravulvar/testicular small incision toward the urogenital diaphragm, guided through the retropubic space along the backside of the pubic bone. Through a second passage along the frontside of the pubic bone, the lead-electrode was placed finally at the genital nerves. SETTING: Department of Anatomy, University Bern, Bern, Switzerland PARTICIPANTS: The study was performed in 5 cadavers (bilaterally) and tested by 10 obstetrics and gynecology surgeons. MEASUREMENTS AND MAIN RESULTS: Positions and courses of the lead electrode in relation to the dorsal nerve of the clitoris/penis were evaluated by dissection of the genitals and showed an optimal parallel course of the lead electrodes to the dorsal nerve from the perforation of the urogenital diaphragm to the crura of the clitoris, with area of the dorsal nerve of the clitoris/penis to the electrode never exceeding 2 mm. Participant surgeons self-evaluated reproducibility and difficulty of the procedure by using a score from 1 to 10 (1, easy/safe; 10, extremely difficult/dangerous). Both reproducibility and difficulty achieved a score of 1 by all participants. CONCLUSIONS: The double-passage genital nerve stimulation procedure is a new peripheral nerve stimulation technique that had a high self-evaluated rate of ease and reproducibility for surgeon participants.

No clitting! We need to talk about clitoris transplantation.

In the last two decades, genital transplants have emerged as another type of quality-of-life transplants. Successful allogenic transplantations of the uterus, ovary, testicle, and penis have all been reported. Yet, there is no discussion of clitoris transplantation in the medical literature, mass media, and everywhere else I searched. This surgery could be used for cisgender women who have a clitoral injury or disease or who have undergone female genital cutting. I examine the gender norms regarding sexuality and reproduction to show how they shape surgical advancements. My point in this paper is not to take a normative position on status of current genital transplantations. Rather, I highlight that their existence is due, at least in part, because they align with dominant gender norms: penis and testicle transplantations reinforce the importance of men's virility and the existence of "normal" male genitalia, whereas uterus and ovary transplantations uphold the conflation of women and reproduction and the strong valuing of women's fertility. That medical advances reflect cultural values is not a new claim. What is new in this paper is the discussion of how sexism norms-regarding the invisibility of the clitoris and the devaluing of women's sexual pleasure- has engendered various types of genital transplants, but not clitoris transplantation.

Abdominoplasty and Clitoris Evaluation: A Prospective Study on Sexual Pleasure in Women Undergoing Abdominoplasty.

INTRODUCTION: Being one of the most practiced procedures in plastic surgery, it is important to foster a better understanding of the effect of anatomical changes in the pubic area after abdominoplasty on sexuality in women. Since to date no study has been performed with this purpose, our aim is to evaluate the impact of the abdominoplasty on sexual pleasure and to perform an objective evaluation of changes in clitoral position and prepubic fat area after this procedure. MATERIALS AND METHODS: A prospective study has been performed in 50 women who expressed a desire to undergo abdominoplasty from January 2021 to December 2021. The primary endpoint was Sexual pleasure assessed by the "Sexuality Assessment Scale" before and 6 months after abdominoplasty in all patients. Furthermore, we evaluated the physical changes of the clitoris (clito-pubic distance, CP distance) and the prepubic fat area on magnetic resonance imaging before and 3 months after abdominoplasty. RESULTS: Patients mean age was of 42 ± 9 years, and mean body mass index of 26 ± 2 kg/m2. A significant difference (P < 0.0001) between sexual satisfaction before and 6 months after abdominoplasty (mean difference +7.4 ± 6.452) was found. Though there was no significant difference between the clito-pubic distance before and after abdominoplasty (mean difference -3.200 ± 2.499 mm; p= 0.0832), a significant difference was found in the size of the prepubic fat area before compared to after abdominoplasty (mean difference -1.714 ± 1.010 cm2; p = 0.0426). However, no significant relationship between these anatomical changes and sexual satisfaction was found. CONCLUSION: Our results show that abdominoplasty is associated with an increase in sexual satisfaction. The changes in the post-operative position of the clitoris were not statistically significant, contrarily to the size of the prepubic fat area, which was significantly modified and could partially explain the improved sexual pleasure. Authors were unable to statistically demonstrate a correlation between those anatomical modifications and sexual pleasure. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Aging effects in the extracellular matrix of the clitoris: A scanning electron microscopic analysis.

OBJECTIVE OF THE STUDY: The present work aims to observe the clitoris' extracellular matrix in young and old women with a scanning electron microscope. MATERIALS AND METHODS: After approval of the local research ethics committee, samples of the clitoris body were obtained from cadavers of women between 20 and 40 old (G1) and from cadavers over the age of 60 (G2). The samples were decellularized with NaOH to maintain the extracellular matrix framework, submitted to silver sputter coating, and observed under a scanning electron microscope. RESULTS: The mean age of the cadavers in G1 was 28 years old and 75±6 years old in G2. The groups were composed of 10 cadavers each. It was observed that the collagen was arranged in a disorganized fashion in the samples from the G2 in several regions. There was also a decrease in elastic fibers that anchored the collagen in these samples. The concentration of collagen showed an increase in the older samples in comparison to the G1 samples. Conclusions Female sexual dysfunction is a condition prevalent in a significantly large portion of women and it is more common in elderly women. It is known that the tumescence mechanism requires integrity of the extracellular matrix. The changes observed herein may alter the function of the organ and are similar to observations in studies of men with erectile dysfunction. CONCLUSION: Female sexual dysfunction is a condition prevalent in a significantly large portion of women and it is more common in elderly women. It is known that the tumescence mechanism requires integrity of the extracellular matrix. The changes observed herein may alter the function of the organ and are similar to observations in studies of men with erectile dysfunction. .

First evidence of hemiclitores in snakes.

Female genitalia are conspicuously overlooked in comparison to their male counterparts, limiting our understanding of sexual reproduction across vertebrate lineages. This study is the first complete description of the clitoris (hemiclitores) in female snakes. We describe morphological variation in size and shape (n = 9 species, 4 families) that is potentially comparable to the male intromittent organs in squamate reptiles (hemipenes). Dissection, diffusible iodine contrast-enhanced micro-CT and histology revealed that, unlike lizard hemiclitores, the snake hemiclitores are non-eversible structures. The two individual hemiclitores are separated medially by connective tissue, forming a triangular structure that extends posteriorly. Histology of the hemiclitores in Australian death adders (Acanthophis antarcticus) showed erectile tissue and strands/bundles of nerves, but no spines (as is found in male hemipenes). These histological features suggest the snake hemiclitores have functional significance in mating and definitively show that the hemiclitores are not underdeveloped hemipenes or scent glands, which have been erroneously indicated in other studies. Our discovery supports that hemiclitores have been retained across squamates and provides preliminary evidence of differences in this structure among snake species, which can be used to further understand systematics, reproductive evolution and ecology across squamate reptiles.

The Suspensory Ligament of the Clitoris: A New Anatomical and Histological Description.

BACKGROUND: The importance of the clitoris as an organ has been neglected by doctors and anatomists over the centuries. Its central role in female sexuality is widely recognized and respected. Although multiple studies have been conducted on the fundiform ligament of the penis, the literature concerning the suspensory ligament of the clitoris is extremely poor. The possibility to describe its complex structure may help us understand female orgasm and sexuality. AIM: Carrying out an anatomical and histological study about the supporting ligaments of the clitoris and in particular the suspensory ligament of the clitoris. STUDY DESIGN: A total of 10 female cadavers were dissected specifically for this study. All the supporting structures of the clitoris were studied, photographed and measured. A histological study of these structures was also carried out. RESULTS: The suspensory ligament of the clitoris is a multidimensional structure consisting of three anatomically and histologically distinct components. The superficial layer originates from the anterior abdominal wall, it is the anatomical extension of the fascia superficialis of the abdomen. It mainly consists of loosely organized elastic fibers, fibroblasts and few loosely organized collagen fibers. The intermediate component also originates from the anterior abdominal wall through the extensions of the abdominal aponeurosis that reach the body of the clitoris. It completely encloses the clitoral body and sends lateral extensions to the labia majora. Histologically, this layer mainly consists of well-organized collagen fibers as well as fibroblasts. The deep component is shorter and extends from the pubic symphysis to the knee of the clitoris and also connects the two crus to the pubic symphysis. It almost exclusively consists of very well organized collagen fibers. CONCLUSION: The suspensory ligament of the clitoris is a multidimensional structure that extends from the anterior abdominal wall to the clitoris. Unlike previous descriptions of the ligament supporting the clitoris, we observed that this structure consists of three anatomically and histologically distinct layers. These new anatomical considerations must be taken into account for any surgery affecting the subcutaneous tissues of the pubis and the abdomen as well as for reconstructive surgery of the clitoris and metoidioplasty. Botter C, Botter M, Pizza C, et al., The Suspensory Ligament of the Clitoris: A New Anatomical and Histological Description. J Sex Med 2022;19:12-20.

Cardiometabolic Diseases and Female Sexual Dysfunction: Animal Studies.

BACKGROUND: The association between erectile dysfunction and cardiometabolic disease is well characterized; men are often diagnosed with cardiovascular disease 2-5 years following the incidence of erectile dysfunction. There is evidence that this relationship may also exist for cardiometabolic diseases and female sexual dysfunction (FSD) - particularly sexual arousal disorders. AIM: To provide a summary of the preclinical literature related to the evidence of FSD in animal models of cardiometabolic diseases and indicate where further research is needed. METHODS: A detailed Medline search of peer-reviewed publications was performed on the associations between animal models of cardiometabolic diseases, FSD and underlying mechanisms. OUTCOMES: A summary of the preclinical evidence of FSD in animal models of cardiometabolic diseases. RESULTS: Common methods for assessing female sexual arousal and physiology in animal models include: 1) behavioral assessments (apomorphine-induced genital vasocongestive arousal; hormone-dependent lordosis), 2) nerve-mediated vaginal and clitoral blood flow, 3) pudendal artery, vaginal and clitoral smooth muscle physiology (vasoreactivity and molecular biology), 4) morphology of genital tissues. Twenty-eight studies examined female animal models of atherosclerosis, hypertension, diabetes (type 1 and 2) and obesity. They showed functional alterations, including decreased lordosis, lubrication, or vaginal and clitoral blood flow, and structural impairments, such as increased clitoral and vaginal fibrosis. Several possible mechanisms have been described including increased TGF-ß, renin angiotensin system and endothelin/rho-kinase signaling, increased reactive oxygen species, and decreased nitric oxide/cGMP signaling. CLINICAL TRANSLATION: In line with existing clinical studies, preclinical evidence supports that cardiometabolic diseases alter female genital tissue's function and structure leading to impaired sexual arousal. STRENGTHS AND LIMITATIONS: This masterclass paper gives an overview of the preclinical research assessing FSD in cardiometabolic disease. Limitations include the small number of studies that have assessed sexual function and arousal in female cardiometabolic animal models. CONCLUSION: Preclinical evidence exists showing cardiometabolic diseases alter the structure and function of female genital tissues. However, similar to clinical studies, there are few studies to draw from, particularly in models of type 2 diabetes, obesity and metabolic syndrome. More studies are required using optimized animal models and methodology to confirm the mechanisms underlying cardiometabolic disease-induced FSD. Angulo J, Hannan JL. Cardiometabolic Diseases and Female Sexual Dysfunction: Animal Studies. J Sex Med 2022;19:408-420.

3D quantitative analysis of normal clitoral anatomy in nulliparous women by MRI.

INTRODUCTION AND HYPOTHESIS: We present a 3D computational approach for automated clitoral measurements. We hypothesized that computationally derived measurements would be comparable and less variable than reported manual measures. METHODS: In this retrospective study, MRIs of 22 nulliparous women age 20-49 years with normal vaginal and clitoral anatomy were collected. Manual segmentations were performed to reconstruct 3D models of the whole clitoris (glans, body, crura, and bulbs) and vagina. The length, width, and volume of the clitoral structures and the distance between the vagina and clitoral structures were calculated. Computed clitoral morphometrics (length, width) were compared to median [range] values from a previously published cadaver study (N = 22) using the median test and Moses extreme reaction test. Calculated distances were compared to mean (± SD) reported by a 2D MRI study (N = 20) using independent t-test and Levene's test. RESULTS: Overall, computed clitoral morphometrics were similar to manual cadaver measurements, where the majority of length and width measures had ~1-2 mm difference and had less variability (smaller range). All calculated distances were significantly smaller and had smaller SDs than manual 2D MRI values, with two-fold differences in the means and SDs. Large variation was observed in clitoral volumetric measures in our cohort. CONCLUSIONS: The proposed 3D computational method improves the standardization and consistency of clitoral measurements compared to traditional manual approaches. The use of this approach in radiographic studies will give better insight into how clitoral anatomy relates to sexual function and how both are impacted by gynecologic surgery, where outcomes can assist treatment planning.

The role of clitoral topography in sexual arousal and orgasm: transperineal ultrasound study.

INTRODUCTION AND HYPOTHESIS: The clitoris has a critical pivotal role in female orgasm and arousal. The aim of this cross-sectional study was to evaluate topographic measurements of the clitoris, as well as to explore potential relationships between the clitoral complex and the orgasm domain of female sexual function, combining transperineal ultrasound with morphometric measurements. METHODS: In sexually active, heterosexual, premenopausal women, three-dimensional transperineal ultrasound imaging was used to measure the subpubic angle, the anterior triangle area (ATA) of the genital hiatus, the levator urethra gap, and the anteroposterior and transverse diameters of the genital hiatus. Mons pubis thickness, clitoris-urethra distance (CUD), clitoris-fourchette distance, and fourchette-perineal body distance were measured using a caliper. Comparison of measurements and correlation with orgasm score were performed. RESULTS: Among the 108 sexually active women, 30 (27.7 %) reported a low orgasm domain score. There were statistically significant differences between the low orgasm group and the control group in the ATA (4.05 vs 3.64 cm2 respectively; p = 0.03), CUD (21 mm; p = 0.04 vs 16.1 mm; p = 0.04), and volume of the glans clitoris (947.7 mm3 vs 1081 mm3; p = 0.02). There was a moderate and inverse correlation between clitoris-urethra distance and orgasm (r = -0.53, p < 0.001), and arousal (r = -0.42 p < 0.001). Broader ATA (OR = 0.47; 95 % CI = 0.23-0.99; p = 0.04) and longer CUD (OR = 0.57; 95 % CI = 0.44-0.73; p < 0.001) were identified as the only independent predictors of orgasm problems. CONCLUSIONS: Longer glans clitoris-urethra distance and broad space for the deep structures of the clitoris is related to difficulty in reaching orgasm and arousal problems.