Andrology-Open Access
Open Access

Penile Morphometrics and Erectile Function in Healthy Portuguese Men

Henrique Pereira^{* *}Correspondence: Henrique Pereira, Department of Psychology and Education, University of Beira Interior, Portugal, Email:

Author info »

Introduction

Human penile morphometry has been the target of much curiosity in all historical and cultural contexts of social evolution, insofar as it traditionally represented considerations associated with hegemonic masculinity, describing values such as potency, fertility, strength, and power [1,2]. More specifically, the size of the penis has been portrayed since prehistoric art, passing through classical Greece and Rome, with an accentuation of its length and thickness, emphasizing the validation of sexual function [3], and creating an overvaluation of culture measurement of the penis, even though it is currently necessary in some situations, for example, in the diagnosis of micro or micro-penis or assessments before penile surgical interventions [4].

The possibility of measuring the length of the penis and evaluating the measurement standards for the human population allows the necessary knowledge to resolve clinical situations related to dissatisfaction with its length [5,6], but, at the same time, may raise concerns about the normativity of this length and, with this, feelings of dissatisfaction or anxiety, such as the small penis syndrome, in which the man is ashamed because of the size of his penis [7], or still, penile dysmorphophobia that describes a condition where the man seeks aesthetic or medical-surgical treatment for believing that his penis is too short, even if both the measure and the sexual function are normal [8,9]. Given the scientific and academic importance of penile morphometry, it is possible to find several studies in literature, focusing mainly on the length and circumference of the penis [10-18], making it possible to state that, according to the systematized data collected in a total of 15.521 men from around the world, on average, the measurements for length are: 9.16 cm (SD=1.57) while flaccid, 13.24 cm (SD=1.89) while stretched, and 13.12 cm (SD=1.66) while erected [19]. The standard measures for the Portuguese man were defined as follows [20], 9.85 cm (SD=1.83) while flaccid and 15.14 cm (SD=2.11) while stretched. Penis length is defined as the linear distance between the pubic symphysis and the tip of the glans [21]. However, the various population surveys demonstrate the lack of universality in the standardization of these measured parameters, depending on the assessment techniques, nationality or race of the participants, the body mass index, disease conditions or others, which can generate difficulties in the adequate treatment of sexual problems, namely, in erectile dysfunction.

A global view of the epidemiology of sexual dysfunction forces us to accept that erectile dysfunction is very prevalent today (33.7% for American men or 47% for middle-eastern men) [22], and on the other hand, some studies show that men who have erectile dysfunction have smaller penises when compared to men without erectile dysfunction [23]. However, this relationship is not clear, since other variables may be mediating this difference such as an overall self-assessment of dissatisfaction with the size of the penis. In fact, men with greater concerns for their penis size have significantly smaller penises than men without such concerns [22], which may justify some interference with sexual function in general and erectile function in particular. Thus, given the lack of Portuguese studies on the relationship between penile morphometry and erectile function, the present study was developed.

Materials and Methods

Participants

1416 Portuguese men participated in this study, 33.40% were single and 38.10% were married, mostly with university degrees. With regard to sexual orientation, 93.40% of the participants identified themselves as heterosexual and 45.80% said they had children. With regard to the place of residence, 88.40% said they lived in an urban environment and the majority (72.30%) said they were employed. With regard to age, the average age was 38.74 years (SD=13.63), ranging from 18 to 65 years old, who said they had no physical or mental health problems diagnosed at the time. All of these data can be better analyzed in (Table 1).

Table 1: Sociodemographic characteristics of the sample participants (n=1416).

Measures

In order to obtain information about the participants, a sociodemographic questionnaire was built which included items such as age, current place of residence, level of education, marital status, sexual orientation, having or not children and the professional situation were included. It was also asked what their current weight and height was to determine the body mass index and whether the penis was circumcised or not. In order to assess the general health status, two self-reported items were formulated ("Do you have any physical health problems diagnosed at this time?" And "Do you have any mental health problems diagnosed at this time?"). Regarding the assessment of penis length and circumference, we opted for the operationalization of Lever et al. [24] based on self-report, which can be a viable source for this type of measurement [25]. The following questions were asked: “How long is your penis erect, in centimetre’s?” and "What is the circumference of your penis when erected, in centimetre’s?". The level of satisfaction with penis morphometry was also assessed with the question: "On a scale of 0-10, indicate how satisfied you are with your penis size and circumference". For the evaluation of erectile function, the Portuguese version of the International Index of Erectile Function-5 (IIEF-5) [26], was used. This is a scale with good psychometric properties, so its use in the Portuguese male population is recommended. The five items are: "How do you rate your confidence in being able to have and maintain an erection?"; "When you had erections with sexual stimulation, how often were your erections hard enough to achieve penetration?"; “During sexual intercourse, how often were you able to maintain your erection after penetration? ” ; “ During sexual intercourse, what was the difficulty you had in maintaining your erection until the end of sexual intercourse?”; and "When you tried to have sex, how often did you feel satisfied?" These five items were submitted to reliability assessment, and a very good Cronbach's alpha score was obtained (0.82), which indicates that the scale has very good internal consistency [27].

Procedures

The survey was conducted between September 2019 and December 2019. Recruitment consisted of online notifications (emails and electronic messages) and advertisements sent to community organizations, mailing lists, and social networks, such as Facebook. Participants responded to the study ’ s outreach online through a website created for this purpose. All advertisements referred participants directly to the online survey, where they were informed that their responses would be anonymous and confidential, in accordance with the Helsinki Declaration of ethical principles concerning research involving human subjects. The first page of the questionnaire explained the study’s objectives and informed participants about how to complete the survey, their freedom to withdraw from the study at any time, and how to contact the author for further information about the study if needed. Confidentiality was ensured by using codes on documents containing study data, by encrypting identifiable data, by assigning security codes to computerized records and by limiting access to identifying information (e.g., IP addresses).

Results

As can be seen in Table 2, men have normative height and weight, with a penis length of 16.75 cm (SD=2.25) and a circumference of 9.56 cm (SD=2.38). The level of satisfaction with penis morphometry is relatively high (7.61 on a scale of 1 to 10; SD=1.87), as well as the total assessment of the level of erectile function (4.21, on a scale of 1 to 5; SD=0.61). The majority of men reported being uncircumcised (81.8%).

Table 2: Results for the descriptive measures (n=1416).

Table 3 describes the results for the association between morphometric measurements, satisfaction with penile morphometry, IIEF-5 items and total level of erectile function, and it can be seen that statistically significant values were obtained (p<0.05) for all associations, using Pearson's coefficients for correlational measures. The following stand out: there is a moderate and negative correlation between penis length and total erectile function, that is, the greater the length of the penis, the lower the erectile function (r=-.242; p<0.05); although there is a significant and positive correlation (despite being weak) between penis circumference and erectile function (r=0.183; p<0.05), there is a strong correlation between length and circumference. On the other hand, penis circumference seems to be more associated to satisfaction with penis morphometry than penis length. It should also be noted that the all five items of the IIEF-5 are strongly correlated with the total IIEF-5.

Table 3: Correlation matrix between penis morphometrics and erectile function.

Also, there are significant differences both for item IIEF-2 and for the total IIEF depending on whether the participants are circumcised or not, as it can be seen in Table 4, where the tstudent statistic for independent samples was used. No differences were found in relation to the morphometric measurements, however, it was found that for both IIEF-2 and total IIFE, uncircumcised men show higher levels of erectile function.

Table 4: Results by circumcision.

Discussion

This study sought to assess the morphometry of the penis in a sample of Portuguese men based on self-report and to determine the degree of association between these measures and erectile function. Thus, the value of 16.75 cm (+/- 2.38 cm) was obtained, which, despite being slightly higher than the value obtained for the Portuguese population [20], is within the normative standard and equal to the French study [28]. The same was true for the circumference. These results were already expected as, even in large-scale studies based on internet collection, most men tend to report median values when measuring their penis size [24], attributing an eventual but not significant bias to the lack of control of the measure, either because there is no standard instrument or because of the subjective look with which each man may have carried out his measurements. Even so, given the size of the sample, the fact that it is differentiated in relation to academic training and perceives itself as healthy, allows us to accept these data as reliable.

Most men said they were very satisfied with the morphometry of their penis, unlike other studies where aspects associated with anxiety about a small penis may have interfered with the results [24-29]. However, these studies were carried out in other cultural contexts or with groups of specific men, for example, men diagnosed with dysmorphophobia or gay men [25-30]. What seems to be linked to good satisfaction with penile morphometry is, precisely, a good erectile function [31] which, in this sample, was also verified.

The most interesting and surprising data of this study concerns the fact that a longer penis length is associated with a lower erectile function, the opposite being true for the perimeter. These results contradict the conclusions of other authors [23-32], but this is probably due to the fact that their results compare men diagnosed with erectile dysfunction under treatment. The fact that larger penises are subject to less erectile function can be explained by age (possible decline in erectile function associated with age and decreased testosterone production) [33], given that, on average, participants are 39 years old, but on the other hand, longer penises may be more prone to damage to spongy and cavernous bodies or Peyronie's disease [34], and sub consequent erectile dysfunction.

Circumcision as being associated with the less erectile function was also an important result. As other studies have concluded [35-37], circumcised men have more erectile problems, not only for mechanical reasons associated with glans exposure and decreased sensitivity, but also for reasons of an emotional or stress-related nature, since in Portugal the overwhelming majority of men are not circumcised, being only those who have some kind of clinical situation, such as phimosis, those who are referred for circumcision.

Very few studies have focused on the study of the relationship between penile morphometry and erectile function, especially in a positive perspective of studying a healthy sample and in Portugal. For this reason, the present study is pioneering, although it is not exempt from some limitations: it is a crosssectional study conducted through the internet, which does not allow the generalization of the results. It will, therefore, be beneficial to carry out more population-based studies and also using clinical populations, in order to explore other possible relationships in order to deepen the understanding of the relationship between penis morphological factors and erectile function.

Conclusion

In conclusion, this study shows that penile morphometry interferes with erectile function, constituting an important source of information and training for professionals working in the field of male sexual health.

Conflict of Interest

The authors report no conflicts of interest concerning the materials or methods used in this review or the findings specified in this paper. The authors have no competing financial interests related to this study.

References

1. Wylie KR, Eardley I. Penile size and the ‘small penis syndrome’. BJU Int. 2007;99:1449-1455.
2. Shaeer O, Shaeer K. Impact of penile size on male sexual function and role of penile augmentation surgery. Curr Urol Rep. 2012;13:285-289.
3. Mattelaer JJ, Ancient Greece and Rome. The Phallus in Art and Culture. History Office European Association of Urology, 2nd Revised edn. Pana Editions, Kortrijk, pp 8-31.
4. Sengezer M, Oztu€rk S, Deveci M. Accurate method for determining functional penile length in Turkish young men. Ann Plast Surg. 2002;48:381-385.
5. Spyropoulos E, Borousas D, Mavrikos S, Dellis A, Bourounis M, Athanasiadis S. Size of external genital organs and somatometric parameters among physically normal men younger than 40 years old. Urology. 2002;60:485-491.
6. Oderda M, Gontero P. Non-invasive methods of penile lengthening: fact or fiction? BJU Int. 2011;107:1278-1282.
7. Veale D, Eshkevari E, Read J, Miles S, Troglia A, Phillips R, et al. Beliefs about penis size: validation of a scale for men ashamed about their penis size. J Sex Med. 2014;11:84-92.
8. Gontero P, Di Marco M, Giubilei G, Bartoletti R, Pappagallo G, Tizzani A, et al. A pilot phase-II prospective study to test the ‘ecacy’ and tolerability of a penile-extender device in the treatment of ‘short penis’. BJU Int. 2009;103:793-797.
9. Ghanem H, Glina S, Assalian P, Buvat J. Management of men complaining of a small penis despite an actually normal size. J Sex Med. 2013;10:294-303.
10. Chrouser K, Bazant E, Jin L, Kileo B, Plotkin M, Adamu T, et al. Penile measurements in Tanzanian males: guiding circumcision device design and supply forecasting. J Urol 2013;190:544-550.
11. Aslan Y, Atan A, Aydın O, Nalçacıoğlu V, Tuncel A, Kadıoğlu A. Penile length and somatometric parameters: a study in healthy young Turkish men. Asian J Androl 2011;13:339-341.
12. Awwad Z, Abu-Hijleh M, Basri S, Shegam N, Murshidi M, Ajlouni K. Penile measurements in normal adult Jordanians and in patients with erectile dysfunction. Int J Impot Res. 2004;17:191-195.
13. Khan S, Somani B, Lam W, Donat R. Establishing a reference range for penile length in Caucasian British men: a prospective study of 609 men. BJU Int. 2012;109:740-744.
14. Ponchietti R, Mondaini N, Bonafè M, Di Loro F, Biscioni S, Masieri L. Penile length and circumference: a study on 3,300 young Italian males. Eur Urol. 2001;39:183-186.
15. Mondaini N, Ponchietti R, Gontero P, Muir GH, Natali A. Penile length is normal in most men seeking penile lengthening procedures. Int J Impot Res. 2002;14:283-286.
16. Promodu K, Shanmughadas K, Bhat S, Nair K. Penile length and circumference: an Indian study. Int J Impot Res. 2007;19:558-563.
17. Söylemez H, Atar M, Sancaktutar A, Penbegül N, Bozkurt Y, Önem K. Relationship between penile size and somatometric parameters in 2276 healthy young men. Int J Impot Res. 2011;24:126-129.
18. Choi S, Park SH, Lee BS, Han J. Erect penile size of Korean men. Venereology. 1999;12:135-139.
19. Veale D, Miles S, Bramley S, Muir G, Hodsoll J. Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15,521 men. BJU Int. 2015;115:978-986.
20. Pereira NM. Estudo do tamanho do pénis na população portuguesa. Rev Int Androl. 2004;2:15-21.
21. Chen J, Gefen A, Greenstein A, Matzkin H, Elad D. Predicting penile size during erection. Int J Impot Res. 2000;12:328-333.
22. Shaeer O, Shaeer K. The Global Online Sexuality Survey (GOSS): The United States of America in 2011. Chapter I: erectile dysfunction among English-speakers. Sex Med. 2012;9:3018-3027.
23. Kamel I, Gadalla A, Ghanem H, Oraby M. Comparing penile measurements in normal and erectile dysfunction subjects. J Sex Med. 2009;6:2305-2310.
24. Lever J, Frederick DA, Peplau LA. Does size matter? Men’s and women’s views on penis size across the lifespan. Psychology of Men and Masculinity. 2006;7:129-143.
25. Grov J, Parsons D, Bimb S. The association between penis size and sexual health among men who have sex with men. Arch Sex Behav. 2010;39:788-797.
26. Pechorro PS, Calvinho AM, Pereira NM, Vieira RX. Validação de uma versão portuguesa do Índice Internacional de Função Eréctil-5 (IIEF-5). Rev Int Androl. 2011;9:3-9.
27. Cortina J. What is coeficient alpha? An examination of theory and applications. J Appl Psychol. 1993;78:98-104.
28. Bondil P, Costa P, Daures J, Louis J, Navratil H. Clinical study of the longitudinal deformation of the flaccid penis and of its variations with aging. Eur Urol. 1991;21:284-286.
29. Veale D, Miles S, Read J, Troglia A, Carmona L, Fiorito C, et al. Phenomenology of men with body dysmorphic disorder concerning penis size compared to men anxious about their penis size and to men without concerns: A cohort study. Body Image. 2015;13:53-61.
30. Veale D, Miles S, Read J, Bramley S, Troglia A, Carmona L, et al. Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorder. Body Image. 2016;17:48-56.
31. Algars M, Santtila P, Jern P, Johansson A, Westerlund M, Sandnabba NK. Sexual body image and its correlates: a population-based study of finnish women and men. Int Sex Health. 2011;23:26-34.
32. Awwad Z, Abu-Hijleh M, Basri S, Shegam N, Mur-shidi M, Ajlouni K. Penile measurements in normal adult Jordanians and in patients with erectile dysfunction. Int J Impot Res. 2005;17:191-195.
33. Nikoobakht MR, Aloosh M, Nikoobakht N, Mehrsay A, Biniaz F, Karjalian MA. The role of hypothyroidism in male infertility and erectile dysfunction. Urology Journal. 2012;9:405-409.
34. Kozacioglu Z, Degirmenci T, Gunlusoy B, Kara C, Arslan M. Effect of tunical defect size after peyronie’s plaque excision on postoperative erectile function: do centimeters matter? Urology. 2012;80:1051-1055.
35. Laumann EO, Paik A, Rosen RC. Sexual dysfunction in the United States. Prevalence and Predictors. JAMA. 1999;281:537-544.
36. Dias J, Freitas R, Amorim R, Espiridião P, Xambre L, Ferraz L. Adult circumcision and male sexual health: a retrospective analysis. Andrologia. 2014;46:459-464.
37. Fink KS, Carson CC, DeVellis RF. Adult circumcision outcomes study: effect on erectile function, penile sensitivity, sexual activity and satisfaction. J Urol. 2002;167:2113-2116.