Age Differences in Clitoral-Vestibular Bulb Anatomy Across the Adult Lifespan

Age Differences in Clitoral-Vestibular Bulb Anatomy Across the Adult Lifespan | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL This is a preprint and has not been peer reviewed. Data may be preliminary. 21 January 2026 V1 View latest version Share on Age Differences in Clitoral-Vestibular Bulb Anatomy Across the Adult Lifespan Authors : Shaniel Bowen 0000-0002-4410-8481 [email protected] , Pamela A Moalli , Arijit Dutta , Krystyna Rytel , Francisco J Gomez Rivas-Vazquez , Holly E Richter , Mark E Lockhart , Sara Perelmuter , Deborah C Marshall , Mercedes Balcells , Elazer R Edelman , and Steven D Abramowitch Authors Info & Affiliations https://doi.org/10.22541/au.176903400.04704533/v1 1049 views 146 downloads Contents Abstract Supplementary Material Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Background: There is sparse normative data on clitoral-vestibular bulb anatomy and how it changes with aging, despite growing evidence of the latter playing a notable role in female sexual function and other pelvic symptoms. Objective: To identify age differences in clitoral-vestibular bulb anatomy (dimensions, position, shape) among women across the adult lifespan. Study Design: This was a retrospective study of pelvic magnetic resonance images of women (≥18 years) without pelvic floor disorder/dysfunction symptom indications (pelvic organ prolapse, urinary incontinence/pain, fecal incontinence/pain, dyspareunia) and with normal pelvic anatomy (radiographically normal reproductive, genitourinary, or gastrointestinal systems). Participants were categorized into the following age groups: Young Adult (18-34 years), Early Midlife (35-49 years), and Older Adult (≥50 years). Axial images of participants in the supine position at rest were acquired for medical indications. The clitoral-vestibular bulb complex, vagina, and urethra were manually segmented to construct 3-dimensional anatomical models. Computational methods quantified clitoral-vestibular bulb dimensions, position, vaginal-urethral distances, and shape (given by principal component scores obtained from a statistical shape model). Age differences in clitoral-vestibular bulb measures were evaluated using Bonferroni-corrected one-way multivariate and univariate analyses of covariance, with adjustments for body mass index and parity. Age-related correlations were assessed using Spearman's rank correlation. Results: A total of 134 women were analyzed (median [range] age, 39 [19-80] years): 47 Young Adult, 46 Early Midlife, and 41 Older Adult women. All Young Adult and Early Midlife women were premenopausal, whereas 27 (71%) of Older Adult women were postmenopausal. Older Adult women had a shorter clitoral body length than Early Midlife women (24.1 mm vs 27.9 mm; P=.006). Overall, smaller vestibular bulb volume was associated with increasing age (P=.04). Older Adult women had a more inferiorly positioned clitoral-vestibular bulb complex (lower in the pelvis) than Early Midlife women (-21.0 mm vs -17.6 mm; P<.001) and Young Adult women (-21.0 mm vs -17.9 mm; P<.001). Across the entire cohort, increasing age correlated with a shorter clitoral body length (ρ=-0.21; P=.01) and vestibular bulb volume (ρ=-0.20; P=.02), and a more posteriorly (ρ=-0.22; P=.01) and inferiorly (ρ=-0.43; P<.001) positioned clitoral-vestibular bulb complex, whereas clitoral volume remained unchanged (ρ=-0.03; P=.73). The shape analysis revealed that age predominantly affected the vestibular bulbs, which became more medially positioned (closer together) (ρ=-0.28; P=.001) and proportionally smaller relative to the clitoris (ρ=-0.28; P=.001) with advancing age. Conclusions: Older age was associated with reduced size and posterior-inferior descent of the clitoral-vestibular bulb complex, with aging primarily affecting the vestibular bulbs compared to the clitoris. Findings demonstrate age-related atrophy and descent of clitoral-vestibular bulb anatomy, which may contribute to sexual function and other pelvic symptoms. GRAPHICAL ABSTRACT: AJOG AT A GLANCE: A. Why was this study conducted? To describe age-related differences in clitoral-vestibular bulb anatomy among women across the adult lifespan. Knowledge of changes in clitoral-vestibular bulb anatomy over time may present insight into their relationships with sexual function and other pelvic symptoms. B. What are the key findings? Aging was associated with a shorter clitoral body, smaller vestibular bulb volume, and a more posteriorly and inferiorly positioned clitoral-vestibular bulb complex, independent of body mass index and parity. Statistical shape analysis revealed that aging predominantly affected the vestibular bulbs, which became more medially positioned (closer together) and proportionally smaller relative to the clitoris. C. What does this study add to what is already known? The evolution of clitoral-vestibular bulb anatomy with age has been ill-defined. Findings demonstrated age-related atrophy and descent of the clitoral-vestibular bulb complex, which may contribute to sexual dysfunction and other pelvic symptoms. INTRODUCTION: The clitoral-vestibular bulb complex is a vital anatomical structure involved in sexual arousal and orgasm. It comprises the clitoris (including the glans, body, and crura) and vestibular bulbs that border the vagina and urethra distally. Together, they play a crucial role in the sexual response. 1–4 Recent studies have shown that a smaller clitoris size and clitoral position farther from the vagina and urethra have been associated with poorer patient-reported sexual function outcomes. 4–7 Additionally, significant (albeit inconsistent) correlations have been found between clitoral morphology and clinical risk factors for sexual dysfunction. 8–13 Sexual dysfunction in men has been well-studied and linked to systemic health and disorders. Conversely, it is a major and under-appreciated condition in women, where roughly 43% of women compared to 31% of men experience sexual problems. 14 Historically, female sexual dysfunction (FSD)—disorders of sexual desire, arousal, orgasm, or pain—have primarily been attributed to psychosocial factors. 15 However, growing evidence has highlighted pathophysiological contributors critical to the female sexual response. 16 For example, aging is a significant risk factor for FSD 17–19 , with sexual difficulties displaying a positive linear or U-shaped relationship with age across the adult lifespan. 20 Furthermore, elevated body mass index (BMI) 21 and higher parity (especially more vaginal deliveries) 22,23 have been associated with FSD symptoms. It is postulated that these patient-related factors may induce biological and biomechanical changes in sexual anatomy (i.e., morphology, position) that contribute to FSD. 24–26 Despite the established relationship between clitoral-vestibular bulb anatomy, sexual function, and clinical determinants of FSD, there is sparse normative data on clitoral-vestibular bulb anatomy and its association with aging and other risk factors of FSD. 27 Most clitoral studies are limited to cadaveric specimens, 28–31 external vulvar or 2-dimensional (2D) image-based measurements, or young monoracial populations. 5,8–13,32–34 Assessment of the full, 3-dimensional (3D) in vivo clitoral-vestibular bulb anatomy across age- and racially diverse populations would establish an improved normative standard of its anatomic variation. 7,35 Such knowledge is essential for obstetric and gynecologic care for women and other individuals with a clitoris [†] (e.g., counseling and decision-making, surgical procedures, FSD diagnosis and management). 27,28,36–40 Therefore, this study aimed to identify the following among women in vivo : (1) age differences in clitoral-vestibular bulb anatomy (dimensions, position, shape) and (2) patient-related risk factors for FSD associated with clitoral-vestibular bulb anatomy. MATERIALS AND METHODS: Study Design and Population: This was a retrospective study of pelvic magnetic resonance imaging (MRI) data of women (age ≥18 years) without pelvic floor disorder/dysfunction symptom indications and with normal pelvic anatomy (i.e., anatomically normal reproductive, genitourinary, or gastrointestinal systems) radiographically verified by P.A.M. and M.E.L. All participants underwent non-contrast pelvic MRI for medical indications (e.g., pelvic/abdominal pain, pelvic cysts/lesions, vaginal/uterine bleeding) ( Supplemental Table 1 ). MRI examinations were performed at the University of Pittsburgh Medical Center Magee-Womens Hospital or the University of Alabama at Birmingham (UAB) between 2005 and 2023. This study was approved by the University of Pittsburgh (#21110161) and UAB (#300008914) Institutional Review Boards to conduct a retrospective chart review of patient characteristics (demographics, medical history) and MRIs based on search terms “female” and “pelvic MRI” until the appropriate sample size was achieved. Data collection and management were performed using REDCap v15.6.1 (Vanderbilt University, Nashville, TN, USA) tools and Microsoft OneDrive. 41,42 Participants were excluded if they had a history of pelvic organ prolapse, prior pelvic surgery, missing BMI/parity data, or vaginal/rectal gel inserted during imaging (as it could distort neighboring anatomy), and any of the following pelvic floor symptom indications: urinary incontinence/pain, fecal incontinence/pain, or dyspareunia. Additional exclusion criteria included incomplete visualization of the entire clitoral-vestibular bulb complex on MRI, presence of pelvic organ prolapse or levator injury on MRI or MRI indications, and any of the following anatomical abnormalities: non-infected urethral diverticuli >3 cm, uterine fibroids >3 cm, or simple/paratubal ovarian cysts >3 cm. Presence of an intrauterine device, thickened endometrial stripe, thrombosed pelvic vein, or hydrosalpinx was permissible. Race (Black, White) and ethnicity (Hispanic/Latina, non-Hispanic/Latina) were self-reported and extracted from medical records. Participants were stratified into the following age groups: Young Adult (YA), 18-34 years; Early Midlife (EM), 35-49 years; and Older Adult (OA), ≥50 years. Patient characteristics included in the analysis were selected based on their reported associations with clitoral-vestibular bulb morphology and literature on FSD. Imaging Protocol: Non-contrast axial MRIs of participants in the supine position at rest were obtained using 1.5- and 3-Tesla (3-T) scanners with a pelvic phased-array coil. Participant-specific MRI specifications are provided in Supplemental Table 2 . Generally, MRI scans comprised of T2-weighted fast relaxation fast spin echo sequences from 1.5-T systems (repetition time, 3000 msec; echo time, 80 msec; field of view, 240 mm; slice thickness, 4 mm; slice gap, 1 mm; flip angle, 90°; matrix, 320×256). Image Segmentation and 3D Reconstruction: MRIs were co-registered and segmented using 3D Slicer v5.8.1 ( www.slicer.org ). 43 First, images were aligned with a 3D pelvic coordinate system based on the pubic symphysis and ischial spines, where the anterior-posterior (Y) and superior-inferior (Z) axes defined the midsagittal plane. 44 Next, the clitoral-vestibular bulb complex, vagina, and urethra were manually segmented according to previous studies. 7,35 Briefly, the clitoral body and crura were separated at the angle formed by (1) the ascending portion of the clitoral body and (2) the medial aspect of the crura. The posterior margin of the clitoral body was denoted when only the body and crura were visible, then extrapolated superiorly-inferiorly to delineate the body from the vestibular bulbs. The inferior border of the clitoral body was demarcated by the last appearance of its midline septum before it extended into the proximal glans. Then, slice segmentations were stacked to create 3D surface models, which were later exported to Mathematica v14.0 (Wolfram Research, Champaign, IL, USA) to quantify clitoral-vestibular bulb measurements and shape. 45 A previous analysis confirmed that scanner field strength and MRI protocol variability did not significantly affect clitoral-vestibular bulb measures or shape during segmentation and shape modeling. Clitoral-Vestibular Bulb Measures: Automated, model-based measurements of the clitoral-vestibular bulb complex were calculated using a custom algorithm ( Figure 1 ). 7,35 For each clitoral component, a bounding box was fitted to its 3D surface model, with its dimensions defining lengths, widths, and thicknesses. The volumes of the clitoral-vestibular bulb complex and its substructures were determined from their respective 3D surface models. The position of the clitoral-vestibular bulb complex was calculated from its centroid relative to the 3D pelvic coordinate system, where its X, Y, and Z coordinates corresponded with its medial-lateral, anterior-posterior, and superior-inferior pelvic position. Distances between the clitoral structures, vagina (anterior vaginal wall), and urethra (urethral centerline) were computed as the minimum surface-to-surface distance between the 3D models. Clitoral-Vestibular Bulb Shape: The shape of the clitoral-vestibular bulb complex was evaluated using statistical shape modeling, a method for describing morphological variability within a population, independent of differences in size, position, and orientation. 46,47 First, an iterative closest-point algorithm initially co-registered patient-specific models with a template model (based on the population mean) using predefined anatomical landmarks. Next, aligned models were imported into Deformetrica v.4.3 ( www.deformetrica.org ), 48 where the template model was morphed into each patient-specific model to create new, smoothed patient-specific models with one-to-one point correspondence ( Figure 2A ). A separate analysis confirmed that the smoothing process preserved the original patient-specific volumes and shapes while minimizing measurement errors introduced by smoothing the model. 35 Then, these new smoothed models were exported to Mathematica for further alignment and uniform scaling (normalization) via Procrustes analysis. Afterwards, a principal component analysis (PCA) using Monte Carlo-based parallel methods was conducted on the corresponding point coordinates to identify the significant principal components (PCs) (i.e., those that explained more variance than the noise in the dataset). 49 Each significant PC is composed of a set of PC scores reflecting where individuals lie along the shape variation described by the PC. A color map visualized shape differences (absolute distances between corresponding points) relative to the population mean, with lighter colors indicating larger shape differences. To better visualize shape differences along each PC, its colored distance map was projected onto shapes ±3 standard deviations (SDs) from the population mean ( Figure 2B ). Sample Size Calculation: Based on previous clitoral studies, 5,6 a minimum sample size of 37 per age group was required to detect a moderate effect size (0.6 SD) at 80% power and 5% significance. 50,51 Statistical Analysis: Two-sided statistical tests at a 0.05 significance level were performed using SPSS v30.0 (IBM Corporation, Armonk, NY, USA). Patient characteristics, presented as medians (25 th , 75 th percentiles) or counts (percentages), were compared between age groups using the Kruskal-Wallis test with post hoc Dunn’s test for continuous variables and the Chi-Square test for categorical variables. Age differences in clitoral-vestibular bulb anatomy were assessed using a one-way multivariate and univariate analyses of covariance, controlling for BMI and parity. Post hoc comparisons were Bonferroni-adjusted. Associations between clitoral-vestibular bulb anatomy and patient characteristics were evaluated using Spearman's rank correlation due to the non-normal distribution of several anatomical variables. RESULTS: Study Population: One hundred and eighty-one women were screened for eligibility; 134 met the inclusion criteria: 47 YA, 46 EM, and 41 OA ( Figure 3 ). Median age was 39.5 years (range, 19-80), BMI was 29.2 kg/m 2 (range, 14.7-67.5), and parity was 2 (range, 0-7). A summary of patient characteristics by age group is shown in Table 1 . Parity was lower in the YA group compared to the EM group (P=.01). All YA and EM women were premenopausal, whereas 27 (71%) of OA women were postmenopausal. There were no differences in race/ethnicity, BMI, smoking status, pulmonary disease prevalence, or hormonal usage. One YA (2%), 2 EM (4%), and 3 OA (7%) women were hormone users. There was a higher proportion of diabetic women in the OA group than in the YA group (P=.04). Clitoral-Vestibular Bulb Measures: Age differences in clitoral-vestibular bulb measurements are presented in Table 2 . A follow-up analysis verified that age differences were not affected by menopausal status. OA women had a smaller clitoral body length than EM women (mean diff=-3.8 mm; P=.006) and a larger crura width and volume than YA women (mean diff=1.0 mm; P=.003; mean diff=625.5 mm 3 ; P=.03). Vestibular bulb volume decreased with aging (P=.04); however, Bonferroni-corrected post hoc analyses revealed no significant pairwise differences between age groups. OA women had a more inferiorly positioned clitoral-vestibular bulb complex than EM women (mean diff=-3.4 mm; P<.001) and YA women (mean diff=-3.1 mm; P<.001). Distance measures were similar between age groups. The correlation analysis ( Table 3 ) demonstrated that across the entire cohort, older age correlated with a smaller clitoral body length (ρ=-0.21; P=.01), larger crura width (ρ=0.28; P=.001), smaller vestibular bulb volume (ρ=-0.20; P=.02), and a more posteriorly (ρ=-0.22; P=.01) and inferiorly (ρ=-0.43; P<.001) positioned clitoral-vestibular bulb complex. Additionally, higher BMI (particularly weight) correlated with larger dimensional and distance measures. Higher parity was associated with a more inferiorly (ρ=-0.33; P<.001) positioned clitoral-vestibular bulb complex, which also correlated with increasing vaginal parity (ρ=-0.24; P=.002). Higher parity, particularly vaginal parity, was also associated with a larger distance between the vagina and clitoral body (ρ=0.22; P=.007) and urethra (ρ=0.22, P=.008). Conversely, cesarean delivery was not associated with clitoral-vestibular bulb position or distance measures. However, more cesarean deliveries did correlate with a larger clitoral glans width (ρ=0.18; P=.04) and thickness (ρ=0.23; P=.01). Clitoral-Vestibular Bulb Shape: Fifteen significant PCs of shape variation of the clitoral-vestibular bulb complex were identified, accounting for 93.7% of the total shape variance ( Supplemental Figures 1-2 ). Overall clitoral-vestibular bulb shape (PCs 1-15 combined) significantly differed by age (P<.001). Follow-up ANCOVAs revealed significant age-related differences and correlations in PCs 4 and 5 ( Supplemental Tables 3-4 ). PC4 denoted variation in the clitoral glans, crura, and vestibular bulbs, where OA women had a more posteriorly positioned glans, longer crura, and more medial vestibular bulbs (closer together) than the EM (P=.04) and YA (P=.01) groups. These shape characteristics also correlated with increasing age (ρ=-0.28; P=.001) ( Figure 4A ). PC5 depicted variation in the clitoral glans, crura, and proportional volume of the clitoris and vestibular bulbs, where the OA group had a more anteriorly positioned glans, wider/thicker and more laterally positioned crura, and smaller vestibular bulb volume relative to the clitoris than the YA group (P=.001). In addition, these shape features correlated with aging (ρ=-0.28; P=.001) ( Figure 4B ). Subsequent correlation analyses illustrated that PC1 and PC3 correlated with BMI and parity, respectively. PC1 described variation of the clitoral body, crura, and vestibular bulbs, where more medial crura and vestibular bulbs, and longer and thinner clitoral body were associated with higher BMI (ρ=-0.30; P<.001)—particularly, larger weight (ρ=-0.29; P<.001), not height (ρ=0.01; P=.90) ( Figure 5A ). PC3 showed variation in the clitoral body and vestibular bulbs, where a thinner clitoral body and larger vestibular bulbs were associated with higher parity (ρ=0.25; P=.004) ( Figure 5B ). COMMENT: Principal Findings: Aging significantly correlated with clitoral-vestibular bulb dimensions and position independent of BMI, parity, and menopausal status. The OA group, compared with the younger age groups, had a shorter clitoral body length, larger clitoral crura width and volume, smaller vestibular bulb volume, and more inferiorly positioned clitoral-vestibular bulb complex. Across the entire cohort, older age was also associated with a more posteriorly positioned clitoral-vestibular bulb complex. Interestingly, while vestibular bulb volume decreased significantly with age, clitoral and clitoral-vestibular bulb complex volumes remained unchanged. Age-related shape differences primarily resided in the vestibular bulbs, where older age correlated with medial displacement and volumetric reduction of the vestibular bulbs relative to the clitoris. Higher BMI was associated with larger clitoral-vestibular bulb dimensions and distance measures, while higher parity correlated with a more inferiorly positioned clitoral-vestibular bulb complex and larger vaginal distance from the clitoral body. Vaginal parity had more significant correlations—specifically with the superior-inferior position of the clitoral-vestibular bulb complex, vaginal-clitoral body distance, and vaginal-urethral distance. BMI, primarily weight, had significant associations with the shape of the clitoral-vestibular bulb complex. Results in Context of Previous Literature: Sexual dysfunction among women has historically been framed as a primarily psychosocial condition. However, recent studies have found significant relationships between female sexual dysfunction and pathophysiological factors such as age and clitoral-vestibular bulb morphology. Consistent with previous studies, aging was associated with smaller clitoral dimensions. 7,10,11 BMI- and parity-related correlations with clitoral measures vary across the literature. Some reported that higher BMI was correlated with a smaller clitoral size, 9,10 while others corroborated our findings of higher BMI being associated with larger clitoral dimensions. 7,11,12 We also found that higher BMI corresponded with larger distances between the clitoris, urethra, and vagina. 9 Lastly, higher parity has been associated with larger clitoral dimensions and distances between the vagina and urethra. 8,9,11 This study found a weak positive correlation between cesarean delivery and clitoral glans size, and that higher (vaginal) parity correlated with larger distances between the clitoral body, vagina, and urethra. We also observed that higher vaginal parity correlated with a more inferiorly positioned clitoral-vestibular bulb complex. Discrepancies with previous literature can be attributed to differences in cohort demographics and clitoral-vestibular bulb measurement methods. First, our cohort is diverse, with a roughly equal distribution of Black and White adult women across a broader age range (19-80), compared to previous cohorts that comprised mainly monoracial (White, Asian) adult women of reproductive age (18-50). 5,8,9,11,13,32,34,35 Secondly, past studies used manual caliper measurements of the external genitalia, which are highly variable due to the tissue's flexibility. 9 Our study used automated, 3D-model-based clitoral-vestibular bulb measurements that are less variable than traditional methods and account for potential confounding variables often ignored in other studies. 7,35 Clinical Implications: Decreases in clitoral size and vestibular bulb volume with age may reflect age-associated structural remodeling and atrophy—potentially involving increased fibrosis, loss of smooth muscle, and reduced blood flow—often coinciding with menopause. 24–26,52–54 A more posterior and inferior position of the clitoral-vestibular bulb complex (farther from the pubic symphysis) with older age suggests a loss of support, likely due to age-related laxity in the connective tissues and muscles that support the clitoris, vestibular bulbs, and pelvic floor. 55,56 Reduced integrity of these supportive structures, which pull the vestibular bulbs laterally, could explain why the bulbs appear to be medially displaced with age, as demonstrated by the shape analysis. Larger clitoral-vestibular bulb dimensions and distances in individuals with higher BMI and weight may be due to aromatization of androgens in fat, increased fat deposition, elevated intra-abdominal pressure, and vascular congestion related to adipose hypertrophy and infiltration. The observed associations with BMI likely reflect systemic tissue effects rather than localized genital changes. A more laterally and inferiorly positioned clitoral-vestibular complex and larger clitoral-urethral-vaginal distances with higher (vaginal) parity can arise from stretching or weakening of connective tissue and muscular supportive structures during vaginal delivery. 23 Notably, smaller size and lower position of the clitoral-vestibular bulb complex have been associated with poorer sexual function outcomes. 4–7 Additionally, aging, elevated BMI, higher parity, and vaginal delivery have been correlated with FSD, although the strength and consistency of these associations vary across studies. 17–23 These reported relationships propose underlying mechanisms for morphological and positional changes in the clitoral-vestibular bulb complex and its supportive structures, which may contribute to FSD. 24-26 Clinically, these findings emphasize the need to regularly evaluate vulvar-clitoral anatomy and genital support structures alongside sexual function outcomes and incorporate them into clinical decision-making in treating FSD—especially among older, elevated BMI, and postpartum populations. 57–60 The current study is unable to specifically comment on sexual function and associated clitoral anatomic findings. Research Implications: Given the established relationships between clitoral-vestibular anatomy, patient-related risk factors of sexual dysfunction, and patient-reported sexual function, more normative data on clitoral-vestibular bulb anatomy and its correlates are vital to improve the understanding and treatment of sexual physiology and dysfunction. Additionally, past studies on clitoral anatomy and sexual function lack racial and ethnic diversity. Thus, future work related to sexual (dys)function should also include morphological assessment of the clitoris (preferably in 3D) among heterogeneous cohorts that include more people from underrepresented populations, while also considering the impact of estrogen usage. Such findings could give a more comprehensive understanding of how the structure and position of clitoral-vestibular bulb anatomy influence the sexual response and contribute to demographic-related disparities in FSD. Strengths and Limitations: Strengths of this study include its well-characterized, age- and racially diverse cohort, and use of 3D imaging and computational analysis methods that improve upon traditional quantitative methods of evaluating clitoral-vestibular bulb anatomy. Study limitations include its retrospective design, lack of longitudinal data, variable MRI quality and specifications, and the absence of data on patient-reported sexual activity, function, and practices. We also acknowledge that this study cannot fully separate the individual contributions of chronological aging and menopause to our morphological findings. Lastly, MRI acquisition occurred in the supine, non-aroused state, and findings may not reflect dynamic anatomical changes during sexual arousal. Conclusions: Clitoral-vestibular bulb size, position, and shape vary with age. Future work will assess racial differences in clitoral-vestibular bulb anatomy and its association with patient-related risk factors of FSD. Outcomes will provide more insight into the relationships between clitoral-vestibular bulb morphology and patient characteristics, elucidating potential clinical determinants and pathophysiological mechanisms of FSD. ACKNOWLEDGMENTS: In addition to our funding sources, we would like to thank the following individuals for their assistance and support towards this study: Megan R. Routzong, PhD (Department of Biomedical Engineering, University of Texas Southwestern Medical Center, Dallas, TX, USA), Deanna Sinex, PhD (Youth Enrichment Services, Inc., Pittsburgh, PA, USA), Stacy Palcsey, BS (Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, USA), Melanie Hoskins, RT (R)(MR)ARRT (Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA), Rachel Durst, MS (Department of Obstetrics, Gynecology & Reproductive Sciences, UPMC Magee-Womens Hospital, Pittsburgh, PA, USA), Lindsey Baranski, MPH (UPMC Magee-Women’s Hospital, Pittsburgh, PA, USA), Leslie A Meyn, PhD (Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA), Sunita Patel (Department Obstetrics and Gynecology, Division of Urogynecology and Reconstructive Pelvic Surgery, University of Alabama at Birmingham, Birmingham, AL, USA), Gianna Morelli, BS (Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, US), Anyssa Oden (Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA; Department of Material Science & Engineering, Carnegie Mellon University, Pittsburgh, PA, USA), Shannon N. Cason, MD (Department of Obstetrics, Gynecology, and Reproductive Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA), Rachel S. Rubin, MD (Department of Urology, Georgetown University Hospital, Washington, DC, USA), Christine M. Vaccaro, DO (Department of Gynecologic Surgery & Obstetrics–Urogynecology Division, Walter Reed National Military Medical Center, Bethesda, MD, USA), Marlene M. Corton, MD, MSCS (Departments of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, USA), Rebecca G. Rogers, MD (Division of Urogynecology, Department of Obstetrics and Gynecology, Albany Medical Center, Albany, NY, USA), Christine Pace, MEd (Koch Institute for Integrative Cancer Research at MIT, Massachusetts Institute of Technology, Cambridge, MA, USA), Noa S. Goodman, PT, DPT, (University of Pittsburgh Medical Center Rehabilitation Institute, Pittsburgh, PA, USA), Magaly Pirotte, MA ( www.positivesexed.org ), Sarah S. Lubrano, DPhil ( www.sarahsteinlubrano.com ), Edelman Lab Harvard-MIT Biomedical Engineering Center (Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA), and the Sexual Medicine Research Team ( www.sexmedresearchteam.com ). AUTHOR CONTRIBUTIONS: S.T.B. had full access to the study data and is responsible for the integrity and accuracy of its analysis. E.R.E. and S.D.A. contributed equally to this study. ● S.T.B. : conceptualization, methodology, data curation, formal analysis, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● P.A.M. : conceptualization, methodology, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● A.D. : data curation, writing (original draft), writing (review and editing). ● K.R. : data curation, writing (original draft), writing (review and editing). ● F.J.G.R.V. : writing (original draft), writing (review and editing). ● H.E.R. : conceptualization, methodology, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● M.E.L. : conceptualization, methodology, formal analysis, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● S.P. : writing (original draft), writing (review and editing) ● D.C.M. : writing (original draft), writing (review and editing), funding acquisition, supervision. ● M.B. : writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● E.R.E .: formal analysis, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. ● S.D.A. : conceptualization, methodology, formal analysis, investigation, writing (original draft), writing (review and editing), funding acquisition, project administration, supervision. CONFLICT OF INTEREST DISCLOSURES: ● P.A.M. reported receiving grants from the National Institutes of Health (NIH) outside the submitted work and the Mellon Foundation; and having patents for Elastomeric Auxetic Membranes for Urogynecological and Abdominal Implantations and Biofabrication of Vaginal Support Using Vaginally Derived Cells, Living Grafts for Pelvic Organ Prolapse Repair, and a Vaginal Hydrogel. ● H.E.R. reported receiving grants from Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), Patient-Centered Outcomes Research Institute (PCORI), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)/Mayo Clinic, and Cosm Medical; data safety monitoring board (DSMB) of BlueWind Medical, Cook Myosite, and Juniper Medical; royalties from UpToDate; board of directors of WorldWide Fistula Fund; editor of International Urogynecology Journal and Current Geriatric Reports; consultant for Neomedic, Coloplast, Palette Life Sciences, Axena, ICA, Laborie, Eli Lilly, and Moremme. ● M.E.L. reported receiving royalties from Elsevier and Jaypee Brothers; participating in the Food and Drug Administration Medical Devices Advisory Panel; and serving as a Society of Radiologists in Ultrasound Executive Board member, American Board of Radiology Ultrasound Certifying Committee chair, deputy editor of the Journal of Ultrasound in Medicine, and a Radiology Editorial Board member. ● D.C.M. reported receiving funding from the National Institutes of Health, Office of the Director, under award DP5OD03187 outside the submitted work. ● S.D.A. reported receiving research support from the NICHD, Renovia Inc., and Sage Inc. ● No other disclosures were reported. FUNDING SOURCES: This work was supported by the University of Alabama at Birmingham Department of Radiology-Center for Clinical and Translational Science Radiology Imaging Development Voucher Program, University of Pittsburgh Clinical and Translational Sciences Institute (UL1-TR-001857), National Academies of Sciences, Engineering, and Medicine’s Ford Foundation Predoctoral Fellowship Program, Massachusetts Institute of Technology School of Engineering Postdoctoral Fellowship Program for Engineering Excellence, and Icahn School of Medicine at Mount Sinai Blavatnik Family Women's Health Research Institute. The content is solely the responsibility of the authors and does not necessarily reflect the official views of these funding sources. ROLE OF THE SPONSOR: No sponsors participated in the study design; collection, management, analysis, and interpretation of the data; writing of the manuscript; or the decision to submit the manuscript for publication. 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Comparison of participant characteristics by age group Overall (N=134) Young Adult (N=47) Early Midlife (N=46) Older Adult (N=41) Characteristics N ≥ 18 years 18-34 years 35-49 years ≥50 years P a Age (years), median (P25, P75) 134 39.5 (30.0, 51.0) 28.0 (24.0, 30.0) b,c 40.5 (38.0, 44.0) b,d 57.0 (52.0, 64.0) c,d <.001 e Non-Hispanic Black, n/N (%) 134 71/134 (53) 26/47 (55) 27/46 (59) 18/41 (44) .36 Non-Hispanic White, n/N (%) 134 63/134 (47) 21/47 (45) 19/46 (41) 23/41 (56) .36 BMI (kg/m 2 ), median (P25, P75) 134 29.2 (24.4, 33.9) 29.1 (24.4, 32.8) 29.8 (23.8, 38.1) 29.1 (24.4, 34.9) .81 Weight (kg), median (P25, P75) 134 81.3 (65.8, 94.3) 78.5 (65.3, 90.7) 82.6 (65.6, 102.9) 81.5 (67.9, 93.7) .61 Height (m), median (P25, P75) 134 1.64 (1.60, 1.70) 1.64 (1.60, 1.70) 1.65 (1.60, 1.72) 1.63 (1.60, 1.69) .56 Gravidity, median (P25, P75) 132 2 (0, 3) 1 (0, 3) b 3 (2, 4) b 2 (1, 3) .007 e Parity, median (P25, P75) 134 2 (0, 3) 0 (0, 2) b 2 (1, 3) b 2 (1, 3) .009 e Cesarean delivery, median (P25, P75) 134 0 (0, 1) 0 (0, 0) 0 (0, 1) 0 (0, 1) .06 Vaginal parity, median (P25, P75) 134 0 (0, 2) 0 (0, 1) c 1 (0, 2) 2 (0, 3) c .04 e Postmenopausal, n/N (%) 128 27/128 (21) 0/45 (0) c 0/45 (0) d 27/38 (71) c,d <.001 e Hormone use, n/N (%) 130 6/130 (5) 1/43 (2) 2/46 (4) 3/41 (7) .52 Current smoker, n/N (%) 134 24/134 (18) 13/47 (28) 8/46 (17) 3/41 (7) .05 Past smoker, n/N (%) 134 44/134 (33) 19/47 (40) 15/46 (33) 10/41 (24) .29 Diabetes, n/N (%) 130 15/130 (12) 1/46 (2) c 7/44 (16) 7/40 (18) c .04 e Pulmonary disease f , n/N (%) 131 12/131 (9) 2/46 (4) 5/45 (11) 5/40 (13) .38 Data are presented as median (25th percentile, 75th percentile) or number/total number (percentage). BMI , body mass index; P , percentile. a P values were obtained using Kruskal-Wallis test for continuous variables and Chi-Square test for categorical variables. b Significant P values for YA vs EM obtained from a post hoc analysis with Bonferroni correction. c Significant P values for YA vs OA obtained from a post hoc analysis with Bonferroni correction. d Significant P values for EM vs OA obtained from a post hoc analysis with Bonferroni correction. e P values of <.05 for differences across all age groups. f Pulmonary disease includes any of the following: asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, and emphysema. TABLE 2. Model-estimated differences in clitoral-vestibular bulb measurements by age group Measurement Overall(N=134) Mean(SE) Young Adult(N=47) Mean(SE) Early Midlife(N=46) Mean (SE) Older Adult(N=41) Mean (SE) P a Dimension Glans Length (mm) 8.4 (0.2) 8.2 (0.4) 8.2 (0.4) 8.8 (0.4) .50 Width (mm) 5.8 (0.1) 5.7 (0.2) 5.8 (0.2) 5.9 (0.2) .75 Thickness (mm) 9.2 (0.1) 9.5 (0.2) 9.0 (0.2) 9.2 (0.2) .30 Volume (mm 3 ) 321.9 (14.3) 316.7 (24.7) 314.7 (24.8) 334.4 (25.9) .83 Body Length (mm) 26.2 (0.5) 26.6 (0.8) 27.9 (0.8) b 24.1 (0.9) b .008 c Width (mm) 8.5 (0.2) 8.6 (0.3) 8.2 (0.3) 8.8 (0.3) .27 Thickness (mm) 14.5 (0.4) 14.8 (0.6) 14.2 (0.6) 14.6 (0.7) .82 Volume (mm 3 ) 2447.1 (94.6) 2654.5 (162.6) 2490.7 (163.4) 2196.1 (171.0) .15 Crura Length (mm) 42.3 (0.8) 41.2 (1.3) 43.7 (1.3) 41.9 (1.4) .42 Width (mm) 7.0 (0.1) 6.5 (0.2) d 7.1 (0.2) 7.5 (0.2) d .005 c Thickness (mm) 10.4 (0.2) 9.8 (0.4) 10.6 (0.4) 10.7 (0.4) .26 Volume (mm 3 ) 2515.0 (97.1) 2148.1 (166.9) d 2623.3 (167.7) 2773.6 (175.5) d .03 c Clitoral-Vestibular Bulb Complex Volume (mm 3 ) 10289.8 (292.8) 10785.5 (503.4) 10089.2 (505.7) 9994.6 (529.3) .50 Clitoris Volume (mm 3 ) 5604.4 (178.0) 5517.4 (306.1) 5717.0 (307.5) 5578.9 (321.8) .90 Vestibular Bulbs Volume (mm 3 ) 4685.4 (159.1) 5268.1 (273.6) 4372.2 (274.9) 4415.8 (287.7) .04 c Position Clitoral-Vestibular Bulb Complex Med-Lat Position (mm) e 0.3 (0.2) 0.0 (0.4) 0.4 (0.4) 0.6 (0.4) .57 Ant-Pos Position (mm) f 81.1 (0.6) 82.0 (1.0) 81.6 (1.0) 79.8 (1.0) .26 Sup-Inf Position (mm) g -18.9 (0.3) -17.9 (0.5) d -17.6 (0.5) b -21.0 (0.5) b,d <.001 c Distance Glans to Urethra (mm) 37.1 (0.6) 36.9 (1.0) 38.5 (1.0) 35.9 (1.1) .19 Glans to Vagina (mm) 38.4 (0.6) 38.1 (1.0) 39.5 (1.0) 37.6 (1.1) .42 Body to Vagina (mm) 21.1 (0.4) 21.1 (0.7) 20.1 (0.7) 22.0 (0.7) .15 Crura to Vagina (mm) 10.5 (0.2) 10.7 (0.4) 9.9 (0.4) 10.9 (0.4) .17 Urethra to Vagina (mm) 5.4 (0.3) 5.3 (0.3) 5.4 (0.3) 6.1 (0.3) .16 Data are presented as mean (standard error). All estimates are derived from linear models with covariates evaluated at the following values: body mass index (kg/m 2 ) = 30.6, parity = 1.7. SE , standard error a Bonferroni-adjusted P values. b Significant P values for EM vs OA obtained from a post hoc analysis with Bonferroni correction. c P values of <.05 for differences across all age groups. d Significant P values for YA vs OA obtained from a post hoc analysis with Bonferroni correction. e A more medial position is given by values closer to zero and a more lateral position is given by values further away from zero. f A more anterior position is given by more positive or larger values and a more posterior position is given by more negative or smaller values. g A more superior position is given by more positive or larger values and a more inferior position is given by more negative or smaller values. TABLE 3. Correlations between clitoral-vestibular bulb measurements and patient characteristic risk factors of female sexual dysfunction Correlation ( P a ) Measurement Age BMI Weight Height Gravidity Parity Cesarean Delivery Vaginal Parity Dimension Glans Length 0.14 (.10) 0.07 (.45) 0.03 (.73) -0.13 (.15) 0.03 (.70) 0.03 (.70) -0.04 (.67) 0.08 (.39) Width 0.12 (.16) 0.30 (<.001) b 0.32 (<.001) b 0.10 (.26) 0.12 (.18) 0.11 (.20) 0.18 (.04) b 0.01 (.91) Thickness 0.03 (.76) 0.35 (<.001) b 0.37 (<.001) b 0.14 (.11) 0.13 (.14) 0.10 (.27) 0.23 (.01) b -0.04 (.62) Volume 0.12 (.17) 0.25 (.003) b 0.25 (.004) b 0.03 (.71) 0.08 (.36) 0.07 (.40) 0.13 (.13) 0.01 (.91) Body Length -0.21 (.01) b 0.29 (<.001) b 0.31 (<.001) b 0.15 (.09) 0.01 (.92) -0.08 (.39) -0.10 (.26) -0.03 (.76) Width 0.09 (.32) 0.02 (.80) 0.04 (.63) 0.12 (.17) -0.02 (.82) 0.00 (.98) 0.02 (.82) -0.02 (.84) Thickness -0.01 (.94) 0.05 (.57) 0.07 (.40) 0.10 (.25) -0.06 (.47) -0.15 (.09) -0.16 (.07) -0.04 (.67) Volume -0.17 (.05) 0.21 (.01) b 0.25 (.003) b 0.20 (.02) b -0.01 (.92) -0.09 (.31) -0.12 (.16) -0.02 (.82) Crura Length 0.01 (.88) 0.30 (<.001) b 0.33 (<.001) b 0.11 (.23) -0.03 (.74) -0.06 (.51) 0.08 (.35) -0.12 (.17) Width 0.28 (.001) b 0.17 (.045) b 0.19 (.03) b 0.12 (.18) -0.08 (.38) -0.05 (.56) 0.00 (.99) -0.06 (.50) Thickness 0.12 (.18) -0.02 (.84) -0.03 (.74) 0.02 (.84) 0.08 (.36) 0.05 (.55) -0.06 (.53) 0.11 (.22) Volume 0.16 (.07) 0.25 (.004) b 0.27 (.002) b 0.12 (.16) 0.07 (.45) 0.03 (.70) 0.03 (.75) 0.02 (.84) Clitoral-Vestibular Bulb Complex Volume -0.12 (.16) 0.33 (<.001) b 0.33 (<.001) b 0.11 (.21) 0.06 (.51) 0.00 (.97) -0.06 (.51) 0.02 (.80) Clitoris Volume -0.03 (.73) 0.27 (.002) b 0.30 (<.001) b 0.17 (.06) 0.06 (.53) -0.02 (.85) -0.05 (.59) 0.02 (.85) Vestibular Bulbs Volume -0.20 (.02) b 0.28 (.99) Position Clitoral-Vestibular Bulb Complex Med-Lat Position c 0.09 (.29) 0.06 (.50) 0.06 (.47) 0.00 (.98) 0.10 (.27) 0.15 (.08) 0.08 (.35) 0.15 (.09) Ant-Pos Position d -0.22 (.01) b 0.08 (.38) 0.18 (.03) b 0.31 (<.001) b -0.01 (.87) -0.06 (.50) 0.08 (.39) -0.13 (.15) Sup-Inf Position e -0.43 (<.001) b -0.06 (.47) -0.06 (.53) 0.00 (.99) -0.26 (.002) b -0.30 (<.001) b -0.07 (.41) -0.26 (.002) b Distance Glans to Urethra -0.07 (.43) 0.43 (<.001) b 0.42 (<.001) b 0.07 (.40) 0.03 (.72) 0.01 (.89) -0.09 (.33) 0.06 (.47) Glans to Vagina -0.05 (.60) 0.46 (<.001) b 0.44 (<.001) b 0.06 (.48) 0.04 (.63) 0.02 (.78) -0.12 (.16) 0.10 (.26) Body to Vagina 0.11 (.22) 0.40 (<.001) b 0.36 (<.001) b -0.05 (.57) 0.17 (.05) 0.22 (.01) b 0.01 (.92) 0.21 (.02) b Crura to Vagina 0.05 (.56) 0.42 (<.001) b 0.31 (<.001) b -0.20 (.02) b 0.09 (.30) 0.14 (.11) 0.01 (.88) 0.12 (.16) Urethra to Vagina 0.20 (.02) b 0.35 (<.001) b 0.36 (<.001) b 0.08 (.35) 0.10 (.27) 0.16 (.06) -0.10 (.25) 0.22 (.01) b BMI , body mass index a Correlation and P values are based on Spearman's rank correlation test. b P values of <.05 c A more medial position is given by values closer to zero, and a more lateral position is given by values further away from zero. d A more anterior position is given by more positive or larger values, and a more posterior position is given by more negative or smaller values. e A more superior position is given by more positive or larger values, and a more inferior position is given by more negative or smaller values. FIGURE/FIGURE LEGENDS: Clitoral-vestibular bulb measurements. ( A ) Coronal and axial clitoral dimension measures of the clitoral glans (orange), body (light blue), and crura (purple). Volumetric measures of the clitoris and vestibular bulbs (light gray) are defined by the volume contained by their respective 3-dimensional surface models. ( B ) Coronal and sagittal views of the clitoral-vestibular bulb complex position (red point) based on the centroid of the 3-dimensional model relative to the pelvic coordinate system, where the X , Y , and Z axes denote the medial-lateral, anterior-posterior, and superior-inferior position. ( C ) Distance measures between the clitoris, urethra (urethral centerline), and vagina (anterior vaginal wall), quantified by the minimum surface-to-surface distances (red areas) between relevant structures. Statistical shape modeling workflow of the clitoral-vestibular bulb complex. ( A ) Generation of smoothed, patient-specific clitoral-vestibular bulb complex models with one-to-one point correspondence. A template model (based on an estimate of the population mean) with predefined anatomical landmarks is morphed into each original patient-specific model to create new patient-specific models with corresponding points for the statistical shape model. ( B ) Identification and visualization of significant principal components (PCs) of clitoral-vestibular bulb complex shape variation. After two iterations of aligning and normalizing the 3-dimensional models, the point coordinates of the surface model were converted from real space into shape space. Then, principal component analysis was performed to reduce the multidimensional shape data to a smaller set of PCs, making it easier to interpret and explain shape variation. To better illustrate shape differences described by each PC, a color map of the point-to-point difference between the population mean shape and each ±3 standard deviation (SD) shape is shown. Lighter colors indicate larger shape differences relative to the population mean and vice versa. PC , principal component; SD , standard deviation Consolidated Standards of Reporting Trials diagram. BMI , body mass index; MRI , magnetic resonance imaging Correlations between age and clitoral-vestibular bulb complex shape. Correlations between age and clitoral-vestibular bulb complex principal component (PC) 4 scores ( A ) and PC 5 scores ( B ). For each PC, the shape distribution explained by the PC is visualized by clitoral-vestibular bulb shapes within three standard deviations (SDs) of the population mean (middle, gray shapes). Lighter colors indicate larger shape differences relative to the population mean, and vice versa. PC , principal component; SD , standard deviation Correlations between patient characteristic risk factors of female sexual dysfunction and clitoral-vestibular bulb complex shape. Correlations between body mass index (BMI)-related factors (weight, height) and clitoral-vestibular bulb complex principal component (PC) 1 scores ( A ) and clitoral-vestibular bulb complex PC 3 scores and parity ( B ). Correlation between clitoral-vestibular bulb complex PC5 scores and age. For each PC, the shape distribution explained by the PC is visualized by clitoral-vestibular bulb shapes within three standard deviations (SDs) of the population mean (middle, gray shapes). Lighter colors indicate larger shape differences relative to the population mean, and vice versa. BMI, body mass index; PC, principal component; SD , standard deviation SUPPLEMENTAL MATERIAL: SUPPLEMENTAL TABLE 1. Participant-specific magnetic resonance imaging indications 01SP001 YA Evaluated for urethral diverticulum 01SP002 EM Rule out urethral diverticulum 01SP006 YA Pelvic pain 01SP007 YA Urethral discomfort/burning 01SP008 YA Possible adenomyosis 01SP011 YA Urethral cyst or diverticulum 01SP012 YA Cyst of Skene duct 01SP013 YA Urethral pain 01SP014 EM Possible urethral diverticulum 01SP016 EM Left adnexal cyst 01SP017 OA Pelvic pressure and frequency 01SP018 OA Urethral diverticulum 01SP019 YA Pain, endometriosis, and bleeding from umbilicus 01SP020 YA Pelvic pain 01SP021 OA Urethral diverticulum 01SP023 YA Mass 01SP024 EM Endometriosis 01SP025 OA Vaginal lump 01SP026 YA Uterine leiomyoma 01SP027 EM Endocavity lesion 01SP028 YA Urethral diverticulum 01SP029 YA Urethral diverticulum 01SP030 YA 01SP033 YA Evaluate for uterovesical fistula 01SP034 YA Urethral diverticulum 01SP035 YA Urethral cyst 01SP036 YA Urethral pain 01SP037 EM Pelvic infection 01SP041 YA Suburethral mass 01SP042 YA Pelvic pressure and pain 01SP044 YA Pelvic pain and dysmenorrhea 01SP046 EM Ovarian cysts 01SP047 OA Left adnexal complex cyst 01SP048 YA LLQ pain after c-section 01SP050 EM LLQ pain after c-section 01SP051 YA LLQ pain and endometriosis 01SP052 OA Urethral stricture 01SP053 OA Vaginal discharge 01SP054 OA LLQ pain 01SP055 OA Discomfort 01SP056 OA Atrophic uterus 01SP059 EM Possible endometriosis 01SP060 EM Ovarian cysts 01SP061 EM LLQ and c-section scar pain 01SP062 EM Abdominal pain 01SP063 EM Abdominal bleeding 01SP064 YA LLQ pain 01SP065 EM LLQ pain 01SP066 EM RLQ pain 01SP068 YA Urethral bulge 01SP069 OA Ovarian cysts 01SP070 EM Evaluate for urethral diverticulum 01SP073 OA Ovarian mass 01SP074 OA Benign ovarian tumors 01SP076 OA Periurethral structure 01SP077 OA Left adnexal cyst/abscess 01SP079 OA Fibroids 01SP080 OA Evaluate for urethral diverticulum 02SP001 YA Abdominal Pain, nausea 02SP002 YA Abnormal Vaginal bleeding 02SP003 YA Worsening pain and swelling of vaginal abscess/Bartholin's cyst 02SP004 YA Abdominal pain; Dysmenorrhea 02SP005 YA Better characterization of uterine/endometrial lesion 02SP006 YA Exam for perianal fistula or abscess 02SP007 YA 02SP008 YA Menorrhagia, lasting about 3.5 weeks per month 02SP009 YA Suspect of urethral diverticulum or vaginal cyst 02SP010 YA Sacral plexiform neurofibroma 02sp011 YA Evaluation of possible urethral diverticulum 02sp012 YA Recurrent urethral diverticulum 02sp013 YA Periurethral mass, possible urethral diverticulum 02sp014 YA EMG suggested right L4 radiculopathy with ongoing denervation in the right vastus medialis 02sp015 YA Uterine anomaly, vaginal septum 02sp016 YA Bilateral pyelonephritis, R ovarian cyst, and cystic pubic body lesion 02sp017 YA Rectovaginal fistula 02sp018 YA Evaluate for AVM 02sp019 YA Lower back pain 02sp020 YA Pelvic inflammatory disease 02sp021 YA 1-year hx of L hip pain, concern for irregularities around the acetabulum and lytic lesion in the GT, L hip. 02sp022 YA Abnormal uterine bleeding 02SP024 EM Uterine artery embolization follow-up 02SP025 EM Fibroid consultation 02SP026 EM Uterine artery embolization consult 02SP027 EM UAE consult for abnormal vaginal bleeding 02SP028 EM Abdominal wall endometriosis, operative planning 02SP029 EM Fibroids 02SP030 EM UAE consult 02SP032 EM Surgical evaluation for a right buttock malignant peripheral nerve sheath tumor. 02SP034 EM UAE consult 02SP035 EM Abdominal pain evaluation 02SP036 EM Suspected recto-vaginal fistula 02SP038 EM Follow-up of ileocolonic Crohn's disease 02SP040 EM Uterine fibroids and endometriosis 02SP041 OA Pelvic pain, post-menopausal 02SP042 OA Pelvic pain 02SP044 OA Evaluation for possible rectovaginal fistula 02SP046 OA Abdominal pain and weight loss 02SP047 OA Possible urethral diverticula. 02SP048 OA Urethral diverticulum 02SP049 OA Periurethral mass, evaluate for diverticulum 02SP050 OA Hematuria and bladder pain 02SP051 OA Ongoing, intermittent pelvic pain for 4-5mo 02SP052 OA Abdominal pain 02SP053 OA Pelvic and perineal pain: Exam unremarkable except pinpoint location of pain. No external lesions palpated. Pelvic floor wnl. Order placed for pelvic MRI to rule out soft tissue or bony lesion. 02SP054 EM Heavy bleeding and irregular periods 02SP055 EM Abnormal uterine bleeding, uterine fibroids, and pelvic congestion 02SP056 EM Kidney transplant check 02SP057 EM Cervical inflammation 02SP060 EM Persistent lower abdomen and pelvic pain 02SP061 EM Failed cannulation of cervix for SIS. Need MRI to characterize fibroids vs adenomyosis 02SP062 EM Increase in heavy bleeding and irregular cycles 02SP063 EM Heavy menstrual bleeding 02SP064 EM Evaluation for UAE 02SP065 EM Heavy vaginal bleeding, considering UAE 02SP066 EM Rectovaginal fistula location identification 02SP067 EM Pelvic abnormality on L side found by CT scan 02SP069 OA RP leiomyosarcoma 02SP070 OA L hip pain and prior soft tissue tumors 02SP071 OA Lower quadrant and pelvic pain 02SP072 OA Pelvic mass 02SP081 OA Delayed graft failure following x-lap and left retroperitoneal hematoma evacuation. 02SP084 OA Chron's colitis with perianal disease 02SP086 OA Grade 1 L5-S1 spondylolisthesis with lumbar facet arthrosis and facet syndrome 02SP087 EM Right vulvar and buttocks pain x2 weeks. MRI to rule out an ischiorectal fossa mass/tumor. 02SP088 EM Pelvic pain, Unknown fluid in cervix 02SP089 EM Sigmoid colon adenocarcinoma finding on colonoscopy 02SP090 EM R ovary and septated cyst 02SP093 EM Pelvic pain suspected stress fracture 02SP099 OA Blockage with emptying bowels, MRI to rule out rectal prolapse/intussusception 02SP100 OA Follow-up on pelvic fluid collection 02SP103 OA Characterization of periurethral mass 02SP104 OA Hepatic neuroendocrine tumor 02SP107 OA Follow-up for anal carcinoma 02SP108 OA Evaluation of hematosalpinx with possible sigmoid colon involvement AVM, arteriovenous malformation; CT, computed tomography; EM, early midlife; EMG, electromyography; GT, greater trochanter; hx, history; L, left; LLQ, left lower quadrant; MRI, magnetic resonance imaging; OA, older adult; R, right; RLQ, right lower quadrant; RP, retroperitoneal; SIS, saline infusion sonogram; UAE, uterine artery embolization; wnl, within normal limits; YA, young adult. SUPPLEMENTAL TABLE 2. Participant-specific magnetic resonance imaging protocol specifications 01SP001 YA FRFSE 1.5 2217 88 32 0.3125 4 1 90 320x224 160 01SP002 EM FRFSE 1.5 3000 90 37 0.4688 4 1 90 320x256 240 01SP006 YA FRFSE 1.5 2717 87 36 0.4688 4 0.8 90 320x256 240 01SP007 YA FRFSE 1.5 2517 89 33 0.3906 4 0.5 90 320x256 200 01SP008 YA FRFSE 1.5 2617 87 36 0.4688 4 0.8 90 320x256 240 01SP011 YA FRFSE 1.5 2317 87 32 0.4688 4 0.8 90 320x256 240 01SP012 YA FRFSE 1.5 1850 89 24 0.3906 4 0.8 90 320x256 200 01SP013 YA FRFSE 1.5 2233 89 30 0.3516 4 0.8 90 320x256 180 01SP014 EM FRFSE 1.5 2683 89 36 0.3516 4 0.8 90 320x256 180 01SP016 EM FRFSE 1.5 2583 87 34 0.4688 5 1 90 320x256 240 01SP017 OA FRFSE 1.5 2250 88 30 0.3906 5 1 90 320x224 200 01SP018 OA FRFSE 1.5 1967 92 30 0.4688 5 1 90 320x224 240 01SP019 YA FRFSE 1.5 2433 86 34 0.4688 4 1 90 320x224 240 01SP020 YA FRFSE 1.5 2550 87 40 0.5469 4 0.8 90 320x256 280 01SP021 OA FRFSE 1.5 2200 88 30 0.3516 5 1 90 320x224 180 01SP023 YA FRFSE 1.5 2550 90 34 0.4688 5 1 90 320x224 240 01SP024 EM FRFSE 1.5 2900 87 38 0.4688 5 1 90 320x256 240 01SP025 OA FRFSE 1.5 3800 107 44 0.9375 5 0 90 256x192 240 01SP026 YA FIESTA 1.5 4 2 25 1.0156 8 1 75 224x160 234 01SP027 EM FRFSE 1.5 2067 89 28 0.4688 4 0.8 90 320x256 240 01SP028 YA 1.5 2383 89 32 0.3906 4 0.8 90 320x256 200 01SP029 YA 1.5 3850 89 26 0.3906 4 0.8 90 320x224 200 01SP030 YA FRFSE 1.5 2650 92 37 0.4688 4 1 90 320x224 240 01SP033 YA FRFSE 1.5 2000 90 26 0.4688 5 1 90 320x224 240 01SP034 YA FRFSE 1.5 3250 88 26 0.3906 5 1 90 320x224 200 01SP035 YA FRFSE 1.5 1883 91 27 0.3125 4 0.8 90 320x256 160 01SP036 YA FRFSE 1.5 3567 87 25 0.4688 4 1 90 320x224 240 01SP037 EM FRFSE 1.5 3500 96 41 1.0156 5 1 90 256x192 260 01SP041 YA FRFSE 1.5 2017 91 30 0.3125 4 0.8 90 320x256 160 01SP042 YA FRFSE 1.5 2617 89 34 0.3906 4 0.8 90 320x256 200 01SP044 YA FRFSE 1.5 2400 88 31 0.4688 4 0.8 90 320x256 240 01SP046 EM FRFSE 1.5 2450 87 34 0.4688 5 1 90 320x256 240 01SP047 OA FRFSE 1.5 2017 90 26 0.4688 5 1 90 320x224 240 01SP048 YA FRFSE 1.5 2600 86 35 0.4883 5 1 90 320x256 250 01SP050 EM FRFSE 1.5 2617 93 34 0.4688 4 0.8 90 320x356 240 01SP051 YA FRFSE 1.5 2717 93 34 0.4297 5 1 90 320x224 220 01SP052 OA FRFSE 1.5 2233 89 30 0.3711 4 0.8 90 320x256 190 01SP053 OA FRFSE 1.5 2250 88 30 0.3906 5 1 90 320x224 200 01SP054 OA FRFSE 1.5 2533 91 37 0.3125 4 0.8 90 320x256 160 01SP055 OA FRFSE 1.5 1817 91 24 0.3125 4 0.8 90 320x256 160 01SP056 OA FRFSE 1.5 2300 90 30 0.4688 5 1 90 320x224 240 01SP059 EM FRFSE 1.5 3567 87 55 0.4688 4 0.8 90 320x256 240 01SP060 EM FRFSE 1.5 2500 90 32 0.4688 5 1 90 320x224 240 01SP061 EM FRFSE 1.5 2450 87 51 0.4688 4 0.8 90 320x256 240 01SP062 EM FRFSE 1.5 2000 92 36 0.5469 5 1 90 320x224 280 01SP063 EM FRFSE 1.5 3167 86 43 0.4883 5 1 90 320x256 250 01SP064 YA FRFSE 1.5 2417 87 38 0.5078 5 1 90 320x256 260 01SP065 EM FRFSE 1.5 1817 88 27 0.4688 4 0.8 90 320x256 240 01SP066 EM FRFSE 1.5 2517 94 40 0.6250 4 0.8 90 320x256 320 01SP068 YA FIESTA 1.5 4 2 22 1.0156 8 1 75 224x160 260 01SP069 OA FRFSE 1.5 2600 87 35 0.4688 5 1 90 320x256 240 01SP070 EM 1.5 2783 9 19 0.4102 4 0.8 90 320x256 210 01SP073 OA 1.5 2617 87 36 0.4688 5 1 90 320x256 240 01SP074 OA 1.5 2033 87 28 0.4688 5 1 90 320x256 240 01SP076 OA 1.5 2083 89 28 0.3906 4 0.8 90 320x256 200 01SP077 OA 1.5 2167 87 29 0.4688 5 1 90 320x256 240 01SP079 OA 1.5 2533 90 33 0.4688 5 1 90 320x256 240 01SP080 OA 1.5 4283 92 27 0.3125 4 1 90 320x256 150 02SP001 YA SSH 3 5460 90 52 0.5500 4 0 90 284x282 220 02SP002 YA TSE 1.5 5053 65 30 0.5417 4 1 90 308x240 260 02SP003 YA 3 6390 87 36 0.3125 3 0.6 160 320x240 200 02SP004 YA BLADE 3 5960 89 55 1.4844 4 1 140 256x256 380 02SP005 YA 3 3790 86 48 0.7500 4 0.8 127 320x240 240 02SP006 YA 3 4980 108 54 0.3438 3.5 0.7 160 320x240 220 02SP007 YA SENSE 80 55 90 02SP008 YA 3 8610 101 44 0.3125 4 1 149 320x224 200 02SP009 YA FRFSE 3 2849 103 54 0.3906 3 0 111 320x224 200 02SP010 YA STIR 1.5 5167 47 41 0.4102 4 0.4 90 288x192 210 02sp011 YA FS 3 4430 87 36 0.3125 4 1 160 320x240 200 02sp012 YA TSE 3 5861 85 40 0.3571 3 0.3 90 324x252 200 02sp013 YA TSE 85 51 0 90 02sp014 YA PD FS 1.5 2470 32 33 1.3672 6 1.5 150 256x192 350 02sp015 YA TSE 1.5 7579 65 45 0.5000 4 1 90 376x294 320 02sp016 YA BH 80 51 90 02sp017 YA FS 3 5200 80 54 0.3438 3.5 0.7 154 320x208 220 02sp018 YA FS 3 4300 77 50 0.7500 4 0.8 152 320x240 240 02sp019 YA PD 1.5 5000 61 30 1.2500 6 1.5 150 256x192 320 02sp020 YA FRFSE 1.5 3214 84 46 0.4688 4 1 160 320x256 240 02sp021 YA PD FS 1.5 4150 40 32 0.7813 6 1.5 90 320x192 400 02sp022 YA 3 6380 86 40 0.8125 4 0.8 145 320x272 260 02SP024 EM 3 8610 101 44 0.3125 4 1 160 320x224 200 02SP025 EM PROP 3 10959 98 45 0.4688 4 1 120 384x384 240 02SP026 EM FS 3 6140 86 55 0.5469 4 1 160 320x240 350 02SP027 EM 3 7830 101 37 0.3125 4 1 160 320x224 200 02SP028 EM PROPELLER 1.5 6241 88 58 0.8789 4 1 160 288x288 450 02SP029 EM TSE 1.5 3000 70 45 0.5357 4 1 90 428x372 300 02SP030 EM BH 80 45 90 02SP032 EM PD 1.5 2550 32 35 1.3281 6 1.5 150 256x153 270.9375 02SP034 EM FRFSE 1.5 2691 86 40 0.4688 4 1 160 256x224 240 02SP035 EM BLADE 3 4540 89 42 1.3672 4 1 140 256x256 350 02SP036 EM 1.5 5341 65 36 0.5417 4 1 90 304x243 260 02SP038 EM FS 3 6431 80 50 0.4883 4 0.4 90 252x246 250 02SP040 EM 3 8610 101 44 0.3125 4 1 160 320x224 200 02SP041 OA BH 80 57 90 02SP042 OA FS 3 4000 77 65 0.3750 3 0.3 145 320x211 240 02SP044 OA 3 3790 86 47 0.3750 3 0.6 147 320x192 240 02SP046 OA SPAIR 1.5 2200 70 60 0.9259 4 1 90 252x217 400 02SP047 OA TSE 1.5 6701 132 40 0.4018 3 0.3 90 288x230 144.054 02SP048 OA 3 6390 87 36 0.3125 3 0.6 160 320x240 200 02SP049 OA FRFSE 1.5 3456 110 28 0.3906 3 3 160 320x256 200 02SP050 OA 3 5500 87 30 0.3125 3 0.6 160 320x240 200 02SP051 OA SPAIR 1.5 5075 70 40 0.7738 4 1 90 332x260 260 02SP052 OA FS 70 43 90 02SP053 OA PD 3 4410 39 55 0.8929 5 1 150 448x242 287.5 02SP054 EM FRFSE 1.5 3000 80 40 0.4688 4 1 160 320x256 240 02SP055 EM BH 80 45 90 02SP056 EM SSH 3 80 47 90 02SP057 EM 3 6570 87 37 0.3125 3 0.6 160 320x240 200 02SP060 EM BH 80 45 90 02SP061 EM VIBE 3 3 1 144 1.0938 2 9 320x224 350 02SP062 EM TSE 1.5 4445 65 28 0.5417 4 1 90 304x243 260 02SP063 EM VIBE 3 3 1 144 1.0938 2 9 320x224 350 02SP064 EM TSE 3 1020 80 44 0.7102 4 1 90 132x111 250 02SP065 EM FSE 3 5729 105 44 0.4688 4 1 111 448x320 240 02SP066 EM FRFSE 3 4409 113 57 0.4688 3 0 111 384x256 240 02SP067 EM TSE 1.5 6528 65 44 0.5417 4 1 90 304x243 260 02SP069 OA SPAIR 1.5 2200 70 60 0.9259 4 1 90 252x217 400 02SP070 OA PD 3 3620 39 54 0.9375 5 1 150 448x242 301.15625 02SP071 OA FS 3 4000 104 27 0.7031 8 2 111 384x224 324 02SP072 OA FRFSE 3 4000 101 51 0.4297 3 0 111 320x288 220 02SP081 OA BTFE 1.5 3 2 50 0.8333 5 1 90 248x245 261.288 02SP084 OA TSE 1.5 6688 100 50 0.4883 4 0.4 90 296x263 250 02SP086 OA PD 1.5 3500 40 36 0.5859 6 1.98 154 256x213 356.25 02SP087 EM FS 1.5 3210 108 36 1.4840 6 1.02 158 256x256 380 02SP088 EM BH 80 45 0 90 0 02SP089 EM ANG 3 6842 98 56 0.3906 3 0.3 111 352x224 200 02SP090 EM SSFSE 1.5 509 88 50 0.7422 4 1 90 320x192 342 02SP093 EM PD 1.5 1950 41 34 1.3281 6 1.5 160 256x192 340 02SP099 OA SSH 3 6026 80 59 0.6875 4 0 90 284x279 220 02SP100 OA 3 6850 101 35 0.3125 4 1 160 320x224 200 02SP103 OA TSE 3 85 51 0 90 0 02SP104 OA PD 1.5 3596 30 28 0.5273 6 2 180 320x192 270 02SP107 OA ANG 3 10700 90 51 0.2813 2 0.2 160 320x238 191.25 02SP108 OA 1.5 132 46 0 0 ANG, angiography; BH, breath-hold; EM, early midlife; FIESTA, fast imaging employing steady-state acquisition; FOV, field of view; FRFSE, fast relaxation fast spin echo; FS, fat-saturation; IDEAL, iterative decomposition of water and fat with echo asymmetry and least-squares estimation; OA, older adult; PD, proton density; PROPELLER, periodically rotated overlapping parallel lines with enhanced reconstruction; SENSE, sensitivity encoding; SM, skeletal muscle mass; SPAIR, spectral attenuated inversion recovery; SSFSE, single shot fast spin echo; SSH, single-shot; STIR, short tau inversion recovery; TE, echo time; TR, repetition time; TSE, turbo spin-echo; VIBE, volumetric interpolated breath-hold examination; YA, young adult. SUPPLEMENTAL FIGURE 1. Axial view of principal components 1-11 of the clitoral-vestibular bulb complex statistical shape model PC , principal component; SD , standard deviation; TV , total [shape] variance SUPPLEMENTAL FIGURE 2. Sagittal view of principal components 1-11 of the clitoral-vestibular bulb complex statistical shape model PC , principal component; SD , standard deviation; TV , total [shape] variance SUPPLEMENTAL TABLE 3. Model-estimated differences in clitoral-vestibular bulb complex shape by age group Young Adult (N=47) Early Midlife (N=46) Older Adult (N=41) PC 18-34 years 35-49 years ≥50 years Mean (SE) Mean (SE) Mean (SE) P All PCs -- -- -- <.001 a PC 1 0.4 (23.0) -48.8 (23.1) 7.9 (24.1) .18 PC 2 2.2 (20.2) 54.6 (20.3) b -51.5 (21.3) b .002 a PC 3 14.7 (17.4) -27.1 (17.5) -7.5 (18.3) .25 PC 4 19.9 (14.2) c 11.3 (14.3) b -41.1 (15.0) b,c .008 a PC 5 31.6 (10.5) c -2.0 (10.5) -24.0 (11.0) c .002 a PC 6 -10.5 (8.4) 7.6 (8.4) 6.7 (8.8) .25 PC 7 6.8 (8.3) -1.1 (8.3) -3.9 (8.7) .66 PC 8 -4.4 (7.4) 9.6 (7.5) -2.2 (7.8) .37 PC 9 6.0 (6.6) -2.4 (6.6) -5.8 (6.9) .45 PC 10 5.0 (6.2) -4.9 (6.2) 2.0 (6.5) .52 PC 11 -2.8 (5.6) 4.0 (5.6) -3.9 (5.9) .57 PC 12 4.1 (5.3) -2.0 (5.3) -2.4 (5.6) .64 PC 13 -0.6 (5.0) 4.2 (5.0) -0.7 (5.3) .74 PC 14 2.3 (4.2) 2.8 (4.2) -7.7 (4.4) .16 PC 15 5.3 (3.9) -4.5 (3.9) -2.2 (4.1) .19 Data are presented as mean (standard error). All estimates are derived from linear models with covariates evaluated at the following values: body mass index (kg/m 2 ) = 30.6, parity = 1.7. PC , principal component; SE , standard error. a P values of <.05 b Significant P values for Early Midlife vs Older Adult obtained from a post hoc analysis with Bonferroni correction. c Significant P values for Young Adult vs Older Adult obtained from a post hoc analysis with Bonferroni correction. SUPPLEMENTAL TABLE 4. Correlations between clitoral-vestibular bulb complex shape and patient characteristic risk factors of female sexual dysfunction Correlation ( P ) a PC Age BMI Weight Height Gravidity Parity Cesarean Delivery Vaginal Parity PC 1 0.08 (.34) -0.30 (<.001) b -0.29 (<.001) b 0.01 (.90) 0.05 (.56) 0.08 (.35) 0.02 (.84) 0.07 (.42) PC 2 -0.13 (.14) -0.01 (.91) 0.04 (.69) 0.12 (.18) 0.04 (.68) -0.03 (.71) 0.08 (.37) -0.10 (.23) PC 3 -0.04 (.63) 0.06 (.48) 0.05 (.61) -0.03 (.75) 0.19 (.03) b 0.25 (.004) b 0.14 (.11) 0.15 (.08) PC 4 -0.28 (.001) b -0.06 (.47) -0.04 (.61) 0.07 (.46) 0.04 (.68) 0.01 (.87) -0.04 (.68) 0.01 (.95) PC 5 -0.28 (.001) b -0.01 (.95) 0.06 (.51) 0.15 (.08) 0.05 (.58) 0.00 (.96) -0.05 (.55) 0.03 (.73) PC 6 0.16 (.06) -0.06 (.50) -0.05 (.56) -0.03 (.75) 0.33 (<.001) b 0.33 (<.001) b 0.18 (.03) b 0.21 (.01) b PC 7 -0.15 (.08) -0.05 (.58) -0.10 (.24) -0.17 (.048) b 0.01 (.92) -0.05 (.59) -0.08 (.37) -0.02 (.78) PC 8 0.01 (.93) -0.15 (.08) -0.16 (.07) -0.07 (.40) 0.02 (.87) -0.03 (.77) -0.04 (.65) 0.05 (.54) PC 9 -0.10 (.27) 0.14 (.10) 0.15 (.08) 0.09 (.28) 0.06 (.47) 0.03 (.70) -0.10 (.23) 0.13 (.15) PC 10 -0.01 (.94) 0.04 (.69) 0.00 (.98) -0.04 (.61) 0.11 (.22) 0.14 (.12) -0.05 (.61) 0.17 (.05) PC 11 -0.02 (.79) -0.19 (.03) b -0.22 (.01) b -0.12 (.18) -0.04 (.65) 0.03 (.74) 0.05 (.53) 0.01 (.91) PC 12 -0.08 (.34) -0.21 (.02) b -0.20 (.02) b 0.06 (.50) -0.06 (.53) -0.08 (.39) 0.01 (.88) -0.09 (.31) PC 13 0.00 (.96) -0.09 (.31) -0.13 (.15) -0.04 (.66) -0.01 (.89) -0.07 (.40) -0.04 (.69) -0.02 (.85) PC 14 -0.16 (.07) 0.02 (.86) 0.02 (.79) 0.05 (.56) 0.03 (.74) 0.02 (.80) 0.09 (.33) -0.06 (.51) PC 15 -0.12 (.17) -0.01 (.87) -0.03 (.73) -0.09 (.28) -0.02 (.85) 0.05 (.59) 0.15 (.08) -0.07 (.43) BMI , body mass index; PC , principal component. a Correlations and P values are based on Spearman's rank correlation test. b P values of <.05 Supplementary Material File (ajog_age_x_clitoral_anatomy_v03.pdf) Download 4.38 MB Information & Authors Information Version history V1 Version 1 21 January 2026 V2 Version 2 10 February 2026 Copyright This work is licensed under a Non Exclusive No Reuse License. Keywords age body mass index clitoral anatomy clitoris dimensions magnetic resonance imaging parity shape statistical shape modeling vestibular bulbs Authors Affiliations Shaniel Bowen 0000-0002-4410-8481 [email protected] Department of Obstetrics, Gynecology, and Reproductive Science, Icahn School of Medicine at Mount Sinai View all articles by this author Pamela A Moalli Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh Magee Women's Research Institute Department of Bioengineering, University of Pittsburgh View all articles by this author Arijit Dutta Department of Anesthesiology, University of Maryland School of Medicine View all articles by this author Krystyna Rytel Vagelos College of Physicians and Surgeons, Columbia University View all articles by this author Francisco J Gomez Rivas-Vazquez Institute for Medical Engineering and Science, Massachusetts Institute of Technology Department of Chemical Engineering, Massachusetts Institute of Technology 15 Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School View all articles by this author Holly E Richter Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, University of Alabama at Birmingham View all articles by this author Mark E Lockhart Department of Radiology, University of Alabama at Birmingham View all articles by this author Sara Perelmuter Weill Cornell Medical College View all articles by this author Deborah C Marshall Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai View all articles by this author Mercedes Balcells Institute for Medical Engineering and Science, Massachusetts Institute of Technology Bioengineering Department, Institut Quimic de Sarria, Ramon Llull University 15 Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School View all articles by this author Elazer R Edelman Institute for Medical Engineering and Science, Massachusetts Institute of Technology 15 Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School View all articles by this author Steven D Abramowitch Department of Anesthesiology, University of Maryland School of Medicine View all articles by this author Funding Information Ford Foundation Metrics & Citations Metrics Article Usage 1049 views 146 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Shaniel Bowen, Pamela A Moalli, Arijit Dutta, et al. 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