¿p#1 Redefining normal: a meta-analysis of vulvar anatomy and the medicalisation of female genital diversity

¿p#1 Objective To conduct a comprehensive meta-analysis on the diversity of normal vulvar anatomy, and to compare these evidence-based norms with the hypertrophy guidelines provided to potential patients seeking surgical intervention for labia majora and minora morphometry. Search Strategy Following PRISMA guidelines, we searched MEDLINE, EMBASE, SCOPUS, and Web of Science (2000-2025) for studies reporting vulvar morphometric data in healthy individuals ≥ ten years Data Collection and Analysis Quality was assessed using the Anatomical Quality Assessment (AQUA) tool. Random-effects meta-analysis calculated pooled means with 95% confidence intervals. Subgroup analyses examined geographic, age-related, and methodological sources of heterogeneity. Publication bias was assessed using funnel plots and Egger’s test (when ≥ ten studies available). PROSPERO ID: CRD42024505302. Main Results Twenty-one studies (n=6070 patients) met inclusion criteria for meta-analysis. Pooled measurements were: labia majora length 83.47mm (95% CI: 78.66-88.28), width 19.48mm (15.31-23.66); labia minora length 48.83mm (44.30-53.36), width 22.38mm (17.51-27.25); clitoral glans width 6.53mm (5.26-7.80). Significant heterogeneity (I 2 >99%) was observed across all measurements. Geographic subgroup analysis revealed statistically significant differences between Asian and North American populations for labia minora dimensions. No significant differences were found between adolescent (10-17 years) and adult populations. Strong positive correlation was identified between BMI and labia minora width (r=0.933). Conclusions This meta-analysis provides the first evidence-based reference ranges for vulvar anatomy, demonstrating substantial natural variation that challenges existing ”hypertrophy” classification systems used for surgical interventions. The study findings support educational interventions and comprehensive counselling as people seeking approaches for addressing genital appearance concerns. Healthcare providers should use these evidence-based ranges when counselling patients, particularly young women, about normal anatomical variation. Funding None. ¿p#1 Redefining normal: a meta-analysis of vulvar anatomy and the medicalisation of female genital diversity ¿p#1 J. Yoon, P. Chau, N. Pather Medical School, The University of Queensland, City, State, Australia (Jisoo Yoon, PhD candidate) Medicine and Health, The University of New South Wales, Sydney, State, Australia (Patrick Chau, PhD); Medical School, The University of Queensland, City, State, Australia (Nalini Pather, PhD); Correspondence to Professor N Pather; [email protected]

Objective To conduct a comprehensive meta-analysis on the diversity of normal vulvar anatomy, and to compare these evidence-based norms with the hypertrophy guidelines provided to potential patients seeking surgical intervention for labia majora and minora morphometry. Search Strategy Following PRISMA guidelines, we searched MEDLINE, EMBASE, SCOPUS, and Web of Science (2000-2025) for studies reporting vulvar morphometric data in healthy individuals ≥ ten years Data Collection and Analysis Quality was assessed using the Anatomical Quality Assessment (AQUA) tool. Random-effects meta-analysis calculated pooled means with 95% confidence intervals. Subgroup analyses examined geographic, age-related, and methodological sources of heterogeneity. Publication bias was assessed using funnel plots and Egger’s test (when ≥ ten studies available). PROSPERO ID: CRD42024505302. Main Results Twenty-one studies (n=6070 patients) met inclusion criteria for meta-analysis. Pooled measurements were: labia majora length 83.47mm (95% CI: 78.66-88.28), width 19.48mm (15.31-23.66); labia minora length 48.83mm (44.30-53.36), width 22.38mm (17.51-27.25); clitoral glans width 6.53mm (5.26-7.80). Significant heterogeneity (I²>99%) was observed across all measurements. Geographic subgroup analysis revealed statistically significant differences between Asian and North American populations for labia minora dimensions. No significant differences were found between adolescent (10-17 years) and adult populations. Strong positive correlation was identified between BMI and labia minora width (r=0.933).

This meta-analysis provides the first evidence-based reference ranges for vulvar anatomy, demonstrating substantial natural variation that challenges existing ”hypertrophy” classification systems used for surgical interventions. The study findings support educational interventions and comprehensive counselling as people seeking approaches for addressing genital appearance concerns. Healthcare providers should use these evidence-based ranges when counselling patients, particularly young women, about normal anatomical variation. Funding None.

Female genital cosmetic surgery; vulva morphometry; vulval anatomy ¿p#1 Introduction The female external genitalia (vulva) encompassing the labia majora, labia minora, glans clitoris, clitoral prepuce and vaginal introitus, is increasing the target of Female Genital Cosmetic Surgery (FGCS). One such procedure is cosmetic labiaplasty, which reshapes the labia minora for aesthetic desire rather that medical need. Globally, labiaplasty ranks as the fastest-growing cosmetic surgical procedure, with alarming trends showing nearly 20% of procedures performed on girls under 18 years of age. 1,2 Worldwide, year-on-year increase for labiaplasties performed in 2019 was 24.1%, 3-7 with a notable uptake by adolescents. 8-10 This exponential growth in FGCS occurs despite professional disagreement from major medical organisations; the American College of Obstetricians and Gynaecologists (ACOG) maintains that these procedures ”are not medically indicated and pose substantial risk”, 11 while similar warnings have been issued by the Society of Obstetricians and Gynaecologists of Canada (SOGC), the International Society for the Study of Vulvovaginal Disease (ISSVD), and other international bodies. 11-13 The FGCS surge reflects multiple contributing factors rooted in sociocultural and psychological influences. Body image is closely connected to the psychology of self-worth, acceptance and belonging, more so in females than males. 14 These feelings are likely intensified by a lack of awareness of the diversity of typical (‘normal’) female anatomy by the opposite sex. Literature demonstrates that pornography consumption is associated with negative genital body image in both men and women, with pornographic media typically depicting smaller labia minora and creating unrealistic perceptions of anatomical norms. 15.16 Pathologising of labia minora hypertrophy has also contributed to this narrative. For example, some authors define a labia minora width exceeding 40-50mm as abnormal and hypertrophic; information often included in patient education. 17-19 In clinical practice, there are two classification systems for labial hypertrophy. 20,21 This paucity of evidence-based reference data on the normal morphometry of the external female genitalia compounds the issues of body image and sociocultural pressure. In 2021, Hayes and Temple-Smith’s systematic review highlighted the issues of a lack of anatomical knowledge. A 2022, a UK study by El-Hamamsy and colleagues demonstrated poor public knowledge of typical female genital anatomy and its variations and concluding that women “undergo operations for conditions that they do not understand”. 22 Despite this concerning landscape, emerging research suggests that brief educational interventions show remarkable effectiveness. In 2023, Fernando and Sharp’s randomised controlled trial of 343 female adolescents demonstrated that a 2-minute video highlighting the range of anatomical diversity significantly improved genital anatomy knowledge, appearance satisfaction, and decreased interest in cosmetic surgery. 15 Furthermore, professional counselling about typical anatomical variation achieves an 87% success in reassuring women initially seeking surgery, suggesting many procedures may be preventable through appropriate education. 13 There is thus a need to better inform the public, in particular potential FGCS consumers, on range of diversity of typical female genital anatomy. It underscores the importance of broader advocacy on ‘women’s’ health to promote body positivity, ensure well-being and female sexual health. To address this evidence gap, this systematic review and meta-analysis aimed to consolidate existing data on typical morphometric diversity of the vulva, with specific emphasis on the labia majora and minora, and establish evidence-based reference guides. Thus, we seek to support social reframing and dialogue on what constitutes ”normal” anatomy of the female external genitalia, provide consolidated data for patient education, and ultimately to modify the drivers for FGCS through enabling informed decision-making.

A systematic review and meta-analysis registered with to the International Prospective Register of Systematic Reviews (PROSPERO; #CRD42024505302) were conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. 23 ¿p#1 Inclusion and Exclusion Criteria Studies with extractable morphometric data on labia majora and labia minora (diameter, width, length), as well as other vulval measurements from healthy individuals born with female genitalia were included in this analysis. Studies with pre-operative measurements of the vulva were included only when it was explicitly described as being absent of pathological presentations. Measurements from individuals ten years or younger were excluded in the analysis as this population was not of primary interest about FGCS. In addition, study participants with ambiguous genitalia, with reported underlying vulval pathologies, and those who have undergone surgical alterations to the external genitalia were also excluded. Search Strategy A comprehensive search of the MEDLINE, EMBASE, SCOPUS and Web of Science (WoS) databases were conducted during 2020 to 2022 and updated on May 25 th 2025. Search strategies were developed in consultation with a medical librarian and included both subject headings and free-text terms. The following search terms and Boolean operators were used and adjusted according to each database : (female genit* OR (vulva* or vulva/) OR (labia majora/ OR labi* maj* OR labium majus/) OR (labium minus/ OR labi* min* OR labia minora/)) adj4 (size* OR length* OR measure* OR morphometr*) . Searches were further limited to “human” studies conducted after the year “2000”. No language restrictions were applied. Additional relevant studies were sourced through Google Scholar or the reference lists of the acquired articles. Search results were imported into Endnote software (X9, Clarivate Analysis, Philadelphia). ¿p#1 Study Selection and Data Extraction Two investigators (JY, NP) independently screened titles and abstracts for inclusion. Full-text eligibility assessment was conducted by two independent investigators (JY; PC) with discrepancies resolved through discussion with a third investigator (NP). Data extraction was performed using a standardised form that included: study characteristics (author, year, country, study design), participant demographics (age, BMI, ethnicity, parity), measurement methodology (clinical examination vs. imaging, examination conditions, equipment used), anatomical landmarks and definitions, and morphometric measurements (length, width, and height of the labia majora, labia minora and other vulval measurements). ¿p#1 Quality Assessment Risk of bias for each article was assessed using the Anatomical Quality Assessment (AQUA) tool. 24 The AQUA tool evaluates six domains: study design appropriateness, sample size justification, subject characterisation, methodology description, statistical analysis, and results reporting. Each domain was rated as low, moderate, or high risk of bias, with an overall quality rating assigned to each study. ¿p#1 Statistical Analysis Statistical analysis was conducted using RStudio (version 1.4.1106; Vienna, Austria). Random effects models were used for all analyses given the anticipated heterogeneity in study population and methodologies. Effect sizes were calculated on pooled means with 95% confidence intervals. Heterogeneity was assessed using Cochran’s Q test (P<0.10 indicating significant heterogeneity) and I 2 statistics (≥75% indicating significant heterogeneity). To identify potential sources of heterogeneity, pre-planned subgroup analyses were performed on: geographical location (Africa, Asia, Europe and North America), two crude life stages [10-17 years (LS1), and ≥18 years (LS2)], measurement methodology (clinical examination vs imaging) and study sample size. ¿p#1 Role of funding source There was no funding course for this study. ¿p#1 PRISMA Search Initial search yielded 3711 articles across all databases, with 3135 remaining after removal of duplicates, and 38 following title and abstract screening. Of these 27 studies met the inclusion criteria for the systematic review, and an additional four studies were identified through reference list screening (Figure 1) (n=31 studies in total). Of these, 21 studies met the criteria for the meta-analysis, with a pooled sample of 6070 individuals (Appendix 1). The remaining ten studies (n=1079 individuals) were included only in systematic synthesis due to a lack of standard deviation reporting, and inability to determine these from available data provided. The PRISMA inclusion process for studies is summarised in Figure 1. ¿p#1 Study Characteristics and Demographics The 21 studies in the meta-analysis ranged widely in sample size (6-1562 subjects) and in the vulval morphometry examined (Table 1). Studies originated from four continental regions (pooled sample): Africa, one ( n =214); Asia, 12 ( n =5030); Europe, four ( n= 756), and North America, four ( n =70). No studies originated from Australia, Oceania and South America despite the comprehensive search, representing a significant information gap. The additional ten studies included in the systematic review (Table 1) originated from: Asia, two ( n =435); Europe, three ( n= 465), and North America, five ( n =179). Of the 21 studies, 20 (95%) recruited participants from clinical settings, with 3 studies recruiting individuals requesting FGCS, potentially introducing selection bias toward women with genital appearance concerns. 25-27 Age demographics varied substantially: three studies included only adolescents (ages 10-17), 14 studies included only adults (≥18 years), and four studies included mixed age groups with non-differentiable data. Mean participant age ranged from 14.35 to 56.4 years across studies. The qualitative data identified in a further ten studies, n= 1079 subjects is described in Appendix 2. ¿p#1 Vulval Morphometry ¿p#1 Labia Majora Ten of the 21 studies reported labia majora length measurements (n=2454 individuals) yielding a pooled mean length of 83.47 mm (95% CI: 78.66-88.28) with high heterogeneity (I² = 99.4%; p<0.0001) (Table 2). Prediction intervals suggest that 95% of future studies would report means between 65.2-101.7mm, indicating substantial expected variation. Six studies reported width measurements (n=740 individuals) with pooled mean 19.48mm (95% CI: 15.31-23.66, I²=99.2%). ¿p#1 Labia Minora A total of 15 out of the 21 studies reported the length of the labia minora (n=4019 individuals), with a pooled mean length of 48.83 mm (95% CI:44.30-53.36; I² =99.4%) (n=4019). Seventeen studies reported width measurements (n=2357 individuals) yielding a pooled mean of 22.38 mm (95% CI: 17.51-27.25; I² =99.8%) (n=2357 individuals), respectively. There was no significance between sides for both length and width. Prediction intervals for labia minora length were 26.4-71.3mm and for width were 2.1-42.7mm, demonstrating extensive normal variation. Individual means for labia minora width ranged from 9.0mm to 31.96mm, with several studies reporting means exceeding traditional ”hypertrophy” thresholds of 40-50mm (1-3). ¿p#1 Glans Clitoris The size of glans clitoris was the second most reported morphometrical parameter reported in 14 of the 21 studies (n=4088 patients) with a pooled mean width of 6.53 mm (95% CI:5.26-7.80) (n=4088 patients) (Table 2). Three studies provided clitoral prepuce length (n=540 patients) with pooled mean 22.50mm (95% CI: 19.04-25.97, I²=98.7%). Table 2 includes a summary of additional vulval morphometric parameters extracted from the studies. ¿p#1 Geographical Variation Analysis Continental sub-group analysis showed statistically significant differences in labia minora length and width between Asia and North America (Appendix 2). Further analysis of these differences with stature was not possible due to the absence of reported stature in these studies. ¿p#1 Age Related Variation Analysis Analysis of differences in life stages, was possible in three and 14 studies, respectively. Four additional studies included adolescents (ages 10-17) and was non-differentiable. When comparing the two groups, no statistical significance between the labia minora length and width was found (Appendix 3). ¿p#1 Body Mass Correlations Correlation of the vulval measurements with Body Mass Index (BMI) found a weak positive correlation to labia minora length (r=0.385) whereas a strong positive correlation with labia minora width (r=0.933). This pattern suggests that weight-related tissue changes preferentially affect labial width rather than length, though the mechanism remains unclear. Asymmetrical Analysis Detailed analysis of left versus right measurements revealed no statistically significant differences for any vulvar structure measured. Mean differences between sides were typically <2mm for all measurements, well within expected measurement error. These findings provide evidence that labial asymmetry represents normal anatomical variation rather than pathological deviation. ¿p#1 Publication Bias Funnel plot analysis was possible for labia minora width (17 studies) and length (15 studies). Visual inspection suggested potential publication bias, with asymmetry favouring studies reporting larger measurements. Egger’s regression test confirmed significant asymmetry for width measurements (p=0.031) but not length (p=0.184). Trim-and-fill analysis suggested three to four potentially missing studies with smaller effect estimates, which would reduce pooled means by approximately 2-3mm. While statistically significant, this potential bias is unlikely to substantially alter clinical interpretation of normal ranges. ¿p#1 Discussion ¿p#1 Main findings and Interpretation This study represents the first comprehensive synthesis of vulvar morphometric data, providing evidence-based reference ranges that challenge social paradigm. Our findings demonstrate that current labial ”hypertrophy” classification systems lack scientific foundation and may pathologise typical ‘normal’ anatomical variation. With pooled labia minora width of 22.38mm and prediction intervals extending to 42.7mm, substantial portions of healthy populations would be classified as ”abnormal” under the traditional 40-50mm thresholds use to guide surgical decision-making. These results have immediate clinical relevance given the alarming increase in labiaplasty procedures from 2015-2021. Our evidence strongly supports ACOG’s position that most women requesting FGCS have typical (‘normal’) anatomy, and that professional counselling might be sufficient in reassuring women initially seeking surgery. This is further supported by Azmoude and colleagues who found that FGCS requests are closely linked with mental wellbeing and body discomfort. 7 Evidence-based education, based on our findings, particularly targeting adolescent and younger women may therefore be helpful in addressing the drastic increase in FGCS in younger people. Challenging current classification systems Our study also found that reported literature is inconsistent on what constitutes labial hypertrophy with some authors defining a labia minora width exceeding 40-50mm as abnormal and hypertrophic. 17-19 Applying these various guides to the findings of this study, the labia minora mean width of 22.38mm would be regarded as below the 40-50mm cutoff for hypertrophy but as ‘Stage 2’ in both hypertrophy classification systems, despite representing pooled data from health individuals. These finding questions the validity of the classification systems for a contemporary population and illustrates how arbitrary thresholds can pathologise normal variation, supporting caution on classifications that “impose a desire for perfection on the younger generation, leading young women to measure their genitalia”. 56 More critically, our finding that several studies reporting means exceeding 30mm demonstrates that current thresholds lack an empirical foundation. We propose that classification systems should focus on functional symptoms rather than arbitrary visual measurements, aligning with professional society recommendations emphasising symptom-based rather than appearance-based indications for surgery. ¿p#1 Geographical and Ethnic Variation Our geographic subgroup analysis revealed significant differences in labia minora length and width between Asia and North America (Table 2) people, with Asian women showing larger mean labia minora dimensions These findings align with emerging research on ethnic differences in genital anatomy, including recent comparative studies between Chinese and Western populations. 57 A possible explanation for this may be difference is stature and size of the individuals. From the data available in the studies analysed, it was not possible to determine the effect of stature on vulvar morphometry. BMI is a global index to screen for obesity and several studies in our meta-analysis documented this index. The strong correlation between BMI and labia minora width (r=0.933) suggests that counselling about genital anatomy should acknowledge how body habitus influences appearance, potentially normalising concerns about anatomical changes with weight fluctuation. However, the weak correlation with length (r=0.385) indicates that labial dimensions are primarily determined by genetic rather than environmental factors, supporting counselling messages about the constitutional anatomical variation. Although Mangla and colleagues also found positive correlations between BMI and vulval measurements, 45 others found no significant influence of BMI on labial morphometry thus further studies are warranted to investigate the relationship between BMI and labial size. 44,52 The substantial overlap between regional ranges (prediction intervals 2.1-42.7mm for width) suggests that individual variation exceeds population-level differences. The absence of data from Australia, Oceania, and South America represents a critical evidence gap. Future research priorities must include diverse population studies to establish truly comprehensive reference standards and avoid perpetuating research inequities that have historically excluded non-Western populations. ¿p#1 Asymmetry vs normal variation Hypertrophy can also be unilateral causing asymmetry of the labia minora. 58 Of concern too, is surgical practices deeming labia minora asymmetry as medically abnormal. 58,59 The morphometric analysis of the labia minora in our study is consistent with studies from Denmark (n=244) and Switzerland (n=657), confirming no statistical significance between between the left and right labium minus. 36,49 This leads to our evidence-based conclusion that labial asymmetry is a characteristic of vulval diversity and not to be regarded as atypical or abnormal. This finding directly challenges clinical practices that classify asymmetry as pathological and supports established research emphasising asymmetry as characteristic of human anatomy generally. These results have immediate counselling implications, providing evidence-based reassurance for patients concerned about asymmetry. Healthcare providers can confidently explain that mild asymmetry (differences <2mm) represents normal variation observed across healthy populations. Implications for Adolescent Populations & educational interventions as clinical priority Our study analysed the morphometric variations in the older paediatric population (10-17 years old). Our unexpected finding of no statistical difference with the adult populations in the width (Appendix 3) and length of the labia minora has implications for clinical practice. This finding may be due to the relatively fewer studies and datasets (n=3) focusing on paediatric cohorts. Nevertheless, given that nearly 20% of labiaplasty procedures are performed on minors, this evidence that adolescent measurements align more with adult ranges that initially perceived suggests that perceived ”abnormalities” in young women likely represent typical variation rather than developmental concerns. Furthermore, the lack of age-related differences has important clinical implications, suggesting that anatomical variation observed in adolescents likely represents permanent rather than transient characteristics. As the age range for those seeking FCGS gets younger, further studies to evidence vulval diversity in younger people are warranted, albeit with careful planning due to the sensitivities of collecting this data in a vulnerable population. The anatomical evidence from this study combined with the psychosocial factors underlying FGCS-seeking behaviours in the adolescent population, is an ethical imperative to provide the appropriate education and reassurance on the typical range of diversity of the vulval anatomy to this population group. This finding supports professional society positions opposing cosmetic procedures in minors and reinforces the role of the clinician in providing educational guidance and counselling to adolescent patients. The striking contrast between rising surgical rates and high success of counselling (87%) 13 highlights educational interventions as a clinical and public health priority. Research demonstrates that brief educational approaches achieve remarkable effectiveness: Fernando and Sharp’s 2-minute video intervention and professional counselling about anatomical diversity both significantly reduced surgical interest while improving body image perceptions. 15 Our evidence-based reference ranges provide the foundation for such interventions and enable healthcare providers to offer specific numerical ranges for typical anatomy (e.g., normal labia minora width ranges from approximately 2-43mm) rather than vague reassurances about ‘normality’. Integration of anatomical diversity education into medical curricula, public health campaigns, and routine healthcare encounters represents an evidence-based approach to addressing the FGCS crisis. Given that educational interventions show effectiveness across age groups, early intervention during adolescence may prevent appearance-related distress from developing. Media Influence and Sociocultural context Our findings must be interpreted within the broader context of media influence on genital appearance perceptions. Research demonstrating that pornography consumption is associated with negative genital body image and that exposure to modified genital images distorts perceptions of ”normal” anatomy underscores the importance of evidence-based education. The fact that experimental studies show 18% shifts in ”normality” ratings after viewing modified images suggests that accurate anatomical education may counteract media-induced distortions. 60 Our reference ranges provide the evidence base for such educational initiatives. Our Recommendations Based on our evidence synthesis, we propose four recommendations for public health and clinical practice initiatives (Figure 2). Study Limitations A major limitation in the metanalysis was the methodological inconsistencies across studies assessing morphometry. The high heterogeneity (I²>99%) reflects the substantial methodological diversity in measurement protocols, anatomical landmarks, and study populations (Appendix 1) and the lack of clear reporting. Publication bias assessment revealed potential overrepresentation of studies with larger measurements, though trim-and-fill analysis suggested this bias would only reduce pooled means by 2-3mm. The most significant limitation involves the lack of measurement standardisation with studies varying in methodological details. Only 14% of studies (three out of 21) reported measurement repeatability, and most lacked detailed protocols enabling replication. Therefore, we advocate for a standardised landmarks recommending the approach by Cao and colleagues be adopted for future studies. 24 Geographic representation limitations, with no data from three continents, restrict global applicability. The concentration of studies in clinical settings rather than population-based samples may introduce selection bias toward women how are concerned about body image and appearance. ¿p#1 Conclusion This meta-analysis represents the first comprehensive synthesis of vulvar morphometric data, providing evidence-based reference ranges that challenge current clinical paradigms and address an urgent public health concern. Our findings demonstrate substantial typical anatomical variation, with pooled labia minora width of 22.38mm (95% CI: 17.51-27.25) and prediction intervals extending to 42.7mm, indicating that existing ”hypertrophy” classification systems lack scientific foundation and may pathologise normal anatomy. Our evidence-based reference ranges provide a critical foundation for clinicians to counsel patients on anatomical diversity. Our findings challenge outdated classifications and support reassurance-based approaches. To address rising the growing crisis in genital appearance-related distress, future research should prioritise standardised measurement protocols, population-based studies avoiding clinical selection bias, and rigorous evaluation of educational interventions. Most critically, integration of these findings into medical education, public health campaigns, and routine clinical practice can prevent unnecessary surgical interventions by reframing anatomical diversity as the norm supporting a shift from pathology-based to evidence-based approaches. ¿p#1 Contributors JY engaged in the screening of titles and abstracts, full-text eligibility assessment, data extraction, writing of the draft manuscript. PC engaged in the full text eligibility assessment for the meta-analysis and systematic review. NP engaged in the screening of titles and abstracts, data extraction, writing and editing of the manuscript. ¿p#1 Declaration of interests We declare no competing interests. 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Culture, Health & Sexuality. 2019: 1 -17. 60. Laan E, Martoredjo DK, Hesselink S, Snijders N, van Lunsen RHW. Young women’s genital self-image and effects of exposure to pictures of natural vulvas. Journal of Psychosomatic Obstetrics & Gynecology. 2017; 38 (4):249-55. Supplementary Material File (appendix 1. characteristics of the studies included in meta-analysis.docx) - Download - 29.66 KB File (appendix 2. geographical subgroups.docx) - Download - 18.62 KB File (appendix 3. forest plots analysis of labia minora width between adult and peadiatric subgroups.docx) - Download - 80.18 KB File (figure 1.docx) - Download - 62.40 KB File (figure 2.docx) - Download - 25.30 KB File (table 1.docx) - Download - 32.92 KB File (table 2.docx) - Download - 20.40 KB Information & Authors Information Version history Copyright This work is licensed under a Non Exclusive No Reuse License.

Authors Metrics & Citations Metrics Article Usage 1944views 387downloads Citations Download citation J. Yoon, P. Chau, Nalini Pather. ¿p#1 Redefining normal: a meta-analysis of vulvar anatomy and the medicalisation of female genital diversity. Authorea. 17 November 2025. DOI: https://doi.org/10.22541/au.176339371.18270462/v1 DOI: https://doi.org/10.22541/au.176339371.18270462/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu.