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Background Penis size is a highly sensitive topic, which has often raised concerns associated with human masculinity and male sexual health. Although data regarding penile dimensions have been published worldwide, little is known about these measurements in South East Asian countries. Objective This study aimed to provide the reference range in penile length, circumference and diameter of Vietnamese men and their variations among men with erectile dysfunction and other diseases. Materials and Methods Information about flaccid length, stretched length, mid‐shaft circumference and glans diameter from the health records of 14,597 men attending the Andrology Consultation was collected. These men were classified into 3 groups being regular reproductive health screening group, sexual dysfunction group and other diseases group. Results We found that penile dimensions follow a non‐parametric distribution, as tested by Kolmogorov‐Smirnov test. The median values are 9.03 cm for flaccid length, 14.67 cm for stretched length, 8.39 cm for mid‐shaft circumference and 2.86 cm for unaroused glans diameter. Length and girth of the penis also changed among the different groups, especially in flaccid state; specifically, men with erectile dysfunction had a greater value in all penile dimensions except for change ratio compared with other groups. Circumcision, which rarely occurs in Vietnam, was associated with a 2 mm reduced penis length. Discussion Findings on correlations between penile dimensions and somatometric parameters from previous studies are questionable and some measurements, such as glans dimension, have not been thoroughly investigated so far. Nevertheless, penile dimensions provide useful insight concerning conditions affecting sexual development and might be a valuable parameter in the assessment of erectile dysfunction. Conclusion Results of this study provide informative materials for the assessment of penile size, including reference values drawn from a large sample of Vietnamese men that can be useful in clinical practice and sexual health education.
Andrology. 2021;00:1–10.
Received: 16 November 2020 
Revised: 28 December 2020 
Accepted: 15 January 2021
DOI: 10.1111/andr.12978
Data from 14,597 penile measurements of vietnamese men
Bac Nguyen Hoai1,2 | Quan Pham Minh2| Thang Nguyen Cao2|
Andrea Sansone3| Elena Colonnello3| Emmanuele A. Jannini3
© 2021 American Society of Andrology and European Academy of Androlog y
1Hanoi Medical University, Hanoi,
2Depar tment of Andrology and Sexual
Medicine, Hanoi Medical University’s
Hospital, Hanoi, Vietnam
3Chair of Endocrinology and Sexual
Medicine (ENDOSEX, Department of
Systems Medicine, Univer sity of Rome Tor
Vergata, Rome, Italy
Bac Nguyen Hoai, Department of
Andrology and Sexual Medicine, Hanoi
Medical University ’s Hospit al, Hanoi
Medical University, No.1 Ton That Tung
street, Dong Da district, Hanoi, Vietnam.
Funding information
EAJ was partially suppor ted by the MIUR
grant 2017S9K TNE_002.
Background: Penis size is a highly sensitive topic, which has often raised concerns
associated with human masculinity and male sexual health. Although data regarding
penile dimensions have been published worldwide, little is known about these meas-
urements in South- East Asian countries.
Objective: This study aimed to provide the reference range in penile length, circum-
ference, and diameter of Vietnamese men and their variations among men with erec-
tile dysfunction and other diseases.
Materials and Methods: Information about flaccid length, stretched length, mid- shaft
circumference, and glans diameter from the health records of 14,597 men attend-
ing the Andrology Consultation was collected. These men were classified into three
groups being regular reproductive health screening group, sexual dysfunction group,
and other disease groups.
Results: We found that penile dimensions follow a non- parametric distribution, as
tested by Kolmogorov- Smirnov test. The median values are 9.03 cm for flaccid length,
14.67 cm for stretched length, 8.39 cm for mid- shaft circumference, and 2.86 cm for
unaroused glans diameter. Length and girth of the penis also changed among the dif-
ferent groups, especially in flaccid state; specifically, men with erectile dysfunction
had a greater value in all penile dimensions except for change ratio compared with
other groups. Circumcision, which rarely occurs in Vietnam, was associated with a
2 mm reduced penis length.
Discussion: Findings on correlations between penile dimensions and somatometric
parameters from previous studies are questionable and some measurements, such as
glans dimension, have not been thoroughly investigated so far. Nevertheless, penile
dimensions provide useful insight concerning conditions affecting sexual develop-
ment and might be a valuable parameter in the assessment of erectile dysfunction.
Conclusion: Results of this study provide informative materials for the assessment of
penile size, including reference values drawn from a large sample of Vietnamese men
that can be useful in clinical practice and sexual health education.
penis size, penile measurements, penile length, glans circumference, erectile dysfunction,
men's health
“Is that big enough?” This is a common, yet sensitive question fre-
quently asked by men requesting andrological consultation during
external genital examination. In fact, a preoccupation with penis size
has existed during the history of human development. Through the
ages, from the artistry work to pornography, the penis has featured
as a symbol of masculinity, virility, fertility, power, and strength.1,2
Starting from 1899, for a century, studies about penile length have
been captivating scientists.3 A lar ge bod y of pa per s con cerning peni s
sizes was published; however, because of differences in methodol-
ogy and patient selection, the results were not consistent and thus
Male genital satisfaction is an important aspect of psychologi-
cal and sexual health, both being possibly affected by either mor-
phological abnormalities or normal penis.4 According to a study on
more than 25,0 00 heterosexual men in the US, at least 45% of men
would like to have a larger penis size and an increased satisfaction
of the partner.2 Concerns over penile size are based on belief in in-
adequately stereotypical ideals leading some men to seek surgical
penile lengthening procedures.5,6 Thus, because the burden of penis
enlargement services was uncontrollable, the definition of a normal
penile size has been created and should be used as educational ma-
terial for patients to correct their choice.
To date, there are only some studies on this topic that have
used population- based sampling method.7 - 9 Moreover, except for
erectile dysfunction,1 , 1 0 - 1 2 differences in penile dimensions be-
cause of different concomitant diseases remain largely unknown.
Therefore, we conducted this study to evaluate reference range
of normal penis size and its alteration among different disease
The Andrology Consultation of Hanoi Medical University's
Hospital is a recognized outpatient clinic for diagnosis and treat-
ment of men's health problems. Patients presenting for various
reasons were firstly evaluated by several experienced androlo-
gists following a systematized protocol including medical and sex-
ual history, physical examination, evaluation of external genitalia
abnormalities, and penile measurements. Further investigations
(such as blood sample, semen analysis, diagnostic imaging) were
used for sp ecific sit uatio ns. Finall y, an andro logic al ex per t took re-
sponsibility for counseling and diagnosing based on International
Statistical Classification of Diseases and Related Health Problems
10th Revision.13 Patient's information used to assess treatment
progression was safely protected in the hospital's record storage
To establish the reference size of penis for Vietnamese men,
approximately 30,000 patients who visited our clinic from January
2014 to December 2019 were screened for this study. Among them,
19,910 men had their penis size measured. To minimize the selection
bias in this study, we excluded young men under 17 years old, men
without the measurement of hormonal concentration, particularly
with testosterone, and testicular ultrasound. Men detected with
genital abnormalities such as penile curvature, hypospadias, phi-
mosis, or pre- pubertal hypogonadism were also excluded. A total of
14,597 men aged 1784 years old who met the inclusion criteria and
had complete penile measurements and serum testosterone concen-
tration assay were selected for data analysis (Figure 1). They were
subsequently classified into 3 groups including regular reproductive
health screening group, sexual dysfunction group, and other disease
groups. Subjects within sexual dysfunction group were further di-
vi d e d into 2 su b- gro ups : men dia gno s e d with er ect ile dy s f unctio n ac-
cording to EAU guidelines14 and men wi th ot her sexua l dys func tio ns.
Because the data about the condition of the foreskin (circumcised or
uncircumcised) was recently upgraded in the hospital's record stor-
age system after 2018, a subgroup of 3938 men among participants
having this information was further investigated. The study was ap-
proved by the ethics council of Hanoi Medical University's Hospital.
Penile dimensions were taken once by 5 well- trained androlo-
gists following a consistent measurement protocol immediately after
penile exposure to minimize temperature effects.15 Penile parame-
ters were measured by a rigid ruler for lengths and a steel caliper
for diameters in the standing position with the penis held parallel
to floor. Penile length was the linear distance from the pubo- penile
junction to the tip of glans along dorsal side by pushing pre- pubic fat
pad to the bone in flaccid and fully stretched state without erection.
Penile diameters were defined as the line between two points on
the circumference of penile shaft's middle point, and corona of glans
that concludes their center. Mid- shaft circumference was calculated
by the formula for perimeter of a circle (Mid- shaft diameter × π).
Change ratio, defined as stretched penile length divided by flaccid
penile length, was also reported. Also, the age, height, and weight
were recorded then body mass index (BMI) was calculated for each
2.1  | Statistical analysis
Data analysis was performed by using R version 3.6.1 for Windows.
Penile dimensions were not normally distributed as result of
Kolmogorov- Smirnov test. All variables were presented in mean,
standard deviation, median, and range. Correlations of differ-
ence factors were computed by Spearman test. The Kruskal- Wallis
test followed by Dunn multiple comparison post hoc tests with
Bonferroni adjustment was performed to detect the differences be-
tween groups of reason for referral. The Wilcoxon signed rank test
was used to compare penile parameters between erectile dysfunc-
tion group and the others. The level of significance was chosen as
p = 0.05. Multivariate linear regression analyses were performed to
detect the effect of anthropometric indicators, testosterone, erec-
tile function, and circumcision history on penile parameters among
the total study population (n = 14,597) and a subgroup of 3938 men
with data about the condition of the foreskin.
General characteristics of 14,597 subjects involved in this study
including age, weight, height, and BMI were described in Table 1.
Distribution of age was similar with respect to the general popula-
tion. Most males came to andrology consultation because of rea-
sons related to reproductive and sexual health (22.6% and 25.6%,
The result of descriptive statistics was shown in Table 2. The
median values of penile dimensions were: flaccid length 9.03 cm
(ranged from 5.10 to 13.20 cm), stretched length 14.67 cm (ranged
from 8.30 cm to 19.90 cm), mid- shaft circumference 8.39 cm (ranged
from 5.34 to 11.3 cm), and glans diameter 2.86 cm (ranged from 1.80
to 4.10 cm). Differences between stretched and flaccid length were
also reported with mean change ratio of 1.63 (ranged from 1.04 to
2.38). All penile dimensions were not normally distributed accord-
ing to Kolmogorov- Smirnov test <0.01. However, these distributions
were approximately symmetric with Skewness between 0.5 and
0.5 as illustrated in Figure 2.
The penile dimensions and age of different groups were pre-
sented in Table 3. Kruskal- Wallis test showed the significant dif-
ferences of age and penile parameters between the three groups
(p < 0.001). Patients with sexual dysfunction had the mean age of
38.5 years (compared with 28.6 years in patients who came for reg-
ular reproductive health screening and 32.4 years in patients with
other diseases). Regarding the penile dimensions, subjects in sexual
dysfunction group presented with greater penile length in both flac-
cid state and stretched state. These men also had increased glans
diameter of 2.91 cm compared with regular reproductive health
screening and other disease groups.
To further investigate the effect of sexual dysfunctions to penile
dimensions, we divided group 2 into men with ED and other sexual
dysfunctions. Our results indicated that patients with ED possessed
bigger penis in all dimensions except for the change ratio compared
with non- ED patients including men in regular reproductive health
screening group, other sexual dysfunction group, and other disease
groups, the differences being statistically significant with p < 0.05
(Table 4). However, the same results were not observed between
other sexual dysfunction group and the remaining groups except for
the difference in stretched length.
Correlation analysis showed that: (1) flaccid length was mod-
erately correlated with stretched length (Spearman's rho = 0.676),
mid- shaft circumference (Spearman's rho = 0.385), glans diame-
ter (Spearman's rho = 0.443), and change ratio (Spearman's rho =
- 0.556); (2) another moderate correlations were found between
stretched length/mid- shaft circumference (Spearman's rho = 0.388),
stretched length/glans diameter (Spearman's rho =0.418), mid- shaft
circumference/glans diameter (Spearman's rho = 0.658). The correla-
tions between penile parameters and age, height, weight, BMI were
significant but relatively weak. No correlations were found between
mid- shaft circumference/age (Table 5).
As results from multivariate linear regression analysis shown in
Tabl e 6, despite st at istic signific ances of all models (p < 0.0 01), the
adjusted R2 was insufficient, ranging between 0.0243 and 0.0713.
Without consideration about circumcision history, increases in
age, height, weight, and total testosterone positively related to
all penile parameters, except for the negative relation between
weight and stretched length and the lack of effects between age
and mid- shaft circumference. Erectile dysfunction was associated
with larger penis size, especially with longer stretched length and
wider glans diameter. Concerning the foreskin, circumcised men
had shorter penile length in both flaccid and stretched states,
whereas mid- shaft circumference and glans diameter were larger
than uncircumcised men.
FIGURE 1 Flow chart of the study.
Reference values for penile dimensions of 14,597 Vietnamese men
were initially established by one of the largest cohor ts to our best
knowledge. Indeed, most of previous repor ts on penis size col-
lected data among Caucasian (Europeans, South Asiansn and North
Africans), while studies in Mongoloids (East Asians, especially South
and South- East Asians) were limited.16,17 Moreover, being penile
lengths and girths affected by methodology, these values were dif-
ferent among studies,15,17 and it was difficult to have an appropriate
range of measurements. This information was essential for adequate
interventions in case of micro- penis, small penis anxiety, or Body
Dysmorphic Disorder that can be treated properly by sex education
and psychosexual counseling.18,19 Thus, results of this present study
could be useful in clinical practice, education purposes, or counsel
for patient with concerns related to penile dimensions.
As part of the andrological evaluation, measurements of penis
in flaccid state could provide accessible informative materials for
both clinicians and patients. Flaccid penis size is an important com-
ponent of male perceptions about masculinity2 and exerts a signifi-
cant influence on male attractiveness.20 In one recent online sur vey,
men reported highest dissatisfaction with the size of their flaccid
penis (27%), followed by length of erect penis (19%) and girth of
erect penis (15%).4 In comparison with results from previous stud-
ies, Vietnamese men have medium flaccid length which was compa-
rable with those from Western Asians (8.96 ± 1.13 cm)3 , 1 1 , 2 1 - 2 3 and
USA (9.01 ± 2.15 cm),24 ,25 whereas mid- shaft penile circumference
was not different with other Asians and smaller than Caucasians
(10.00 ± 0.75 cm of Italians and 9.52 ± 0.52 cm of US Americans)
(Table 7). However, it should be noted that the penile circumference
was here calculated from mid- shaft diameter with assumption sug-
gested by Spyropoulos et al26 that may need fur ther studies to be
confirmed. Despite methodological variations, differences in size
of penis might not adhere to ordinary evolution principle suggested
by Rushton's theory that Mongoloids had smallest penis compared
with other populations.17 Further multicenter studies with standard
penile measurement technique are needed to discover racial effects
and related factors that change the penis size as it is for many other
body parameters.
Glans dimensions were usually underrated and ignored in studies
about penis size. As part of the phallus, glans penis acts protectively,
TABLE 1 General characteristics of 14,597 subjects.
Participant distribution
n (%) Mean (SD)
Age (years) 33.1 (10.7)
1 7 2 9 6735 (46.1%)
3 0 4 4 5741 (39.3%)
4 5 5 9 1670 (11.4%)
≥60 451 (3.1%)
Height (cm) 167.8 (5.52)
Weight (kg) 63.1 (8.57)
BMI (kg/m2) 22.4 (2.60)
BMI <18.5 847 (5.8%)
18.5 ≤ BMI <23 7937 (54.4%)
23 ≤ BMI <25 3578 (24.5%)
25 ≤ BMI <27.5 1790 (12.3%)
27.5 ≤ BMI <30 354 (2.4%)
BMI ≥30 91 (0.6%)
Serum total testosterone
concentration (nmol/L)
16.9 (6.00)
<12 nmol/L 2932 (20.1%)
≥12 nmol/L 11,665 (79.9%)
Circumcised 221 (5.6%)
Uncircumcised 3717 (94.4%)
Yes 3098 (22.4%)
No 10,756 (77.6%)
Marriage statusc
Single 4808 (33.1%)
Married 9717 (66.9%)
Reason for referral
Regular reproductive
health screening
3302 (22.6%)
Sexual dysfunction 3732 (25.6%)
Other 7563 (51.8%)
Abbreviations: SD, standard deviation.
aFor 3938 individuals.
bFor 13,854 individuals.
cFor 14,525 individuals.
TABLE 2 Descriptive statistics for penile parameters.
Mean −2SD +2SD Min Max Median
percentile Skew Kurtosis
Flaccid length (cm) 9.0 3 7. 0 1 11. 05 5.10 13.20 8.90 7. 5 0 10.70 0.27 0.42
Stretched length (cm) 14.67 11.99 1 7. 35 8.30 19.90 14.70 12.50 16.70 0.17 0.28
Mid- shaft circumference
8.39 6.55 10.23 5.34 11.3 8.16 6.91 10.05 0.18 0.27
Glans diameter (cm) 2.86 2.22 3.50 1.80 4.10 2.80 2.40 3.40 0.28 0 .12
Change ratio 1.63 1.37 1.89 1.04 2.38 1.63 1.42 1.86 0.27 0. 55
Abbreviations: SD, standard deviation.
absorbing forces during coitus27 and def ines the unique shape of the
penis. In our knowledge, there were several studies reporting flaccid
glans length,8,15, 26 but only one interesting Chinese study that pre-
sented an average flaccid glans diameter of 2.6 ± 0.3 cm, similar with
our findings.15 These results were essential for the achievement of
knowledge for penile plastic surgeries or augmentations for which
construction of glans with adequate size would be required.
Stretched length could be used effectively to predict penile size
during erection without intra- cavernous injection,23, 24 which is not
suitable for every individual in usual clinical setting.2 3,24 Chen et al.
FIGURE 2 Distribution of penile
TAB LE 3  Mean and standard deviation of penile parameters from three main disease groups.
NAge (years)
Flaccid length
length (cm)
Mid- shaft
circumference (cm)
Glans diameter
(cm) Change ratio
Group 1 3302 28.6 (6.4 4) 8.99 (1.01)A14.6 (1.39) 8.42 (0.95)A2.84 (0.31)A1.63 (0.13) A
Group 2 3732 38.5 (12.3) 9.09 (1.01) 14.8 (1.30) 8.43 (0.94)A2.91 (0.33) 1.63 (0.14) AB
Group 3 7563 32.4 (10.1) 9.02 (1.01)A14.7 (1.32) 8.36 (0.90) 2.85 (0.31)A1.6 4 (0.14) B
Note: No significant differences were found between groups shared the same letter.
Group 1: regular reproductive health screening (RRHS); Group 2: sexual dysfunctions; Group 3: other diseases (OD).
TABLE 4 Comparisons between penile parameters of erectile dysfunction and the other groups.
NAge (years)
Flaccid length
length (cm)
Mid- shaft
circumference (cm)
Glans diameter
ED 1897 44.0 (12.9) 9.19 (1.03) 14.9 (1.25) 8.48 (0.94) 2.96 (0.33) 1.63 (0.14)
N o n - E D 12700 31.5 (9.25)# 9.01 (1.00)# 14.6 (1.34)# 8.38 (0.92)# 2.85 (0.31)# 1.63 (0.13)
OSD 1835 32.9 (8.71)#8.99 (0.98)# 14.6 (1.33)# 8.37 (0.94)# 2.86 (0.32)# 1.63 (0.13)
RRHS 3302 28.6 (6.4 4) # 8.99 (1.01)# 14.6 (1.39)# 8.42 (0.95)*2.84 (0.31)# 1.63 (0.13)
OD 7563 32.4 (10.1)# 9.02 (1.01)# 14.7 (1.32) # 8.36 (0.90)# 2.85 (0.31)# 1.64 (0.14)
Abbreviations: ED, erectile dysfunction; RRHS, regular reproductive health screening; OSD, other sexual dysfunction (without erectile dysfunction),
OD, other diseases.
#p < 0.001— Compare with ED.
*p < 0.05— Compare with ED.
Mid- shaft
Age 0.090*0.021#0.012 0.160*−0.093*
Weight 0.084*0.051*0.202*0.191*−0.054*
Height 0.095*0.144*0.14 4*0.108*0.037*
BMI 0.046*−0.022#0.156*0.16 3*−0.087*
Flaccid length 1.000
Stretched length 0.676*1.000
Mid- shaft circumference 0.385*0.388*1.000
Glans diameter 0.443*0. 418*0.658*1.000
Change ratio −0.556*0.174*−0.095*−0.134*1.000
#p < 0.01.
*p < 0.001.
TABLE 5 Spearman's rho for
correlation between variables.
TAB LE 6  Multivariate linear regression analysis for predict the change of each penile parameter with and without the effect of
Total study population (n = 14,597) Subgroup (n = 3938)
length (cm)
Mid- shaft
Flaccid length
length (cm)
Mid- shaft
β coefficient β coefficient
Age (year) 0.0109*0.0057*−0.0004 0.0142*0.0085*0.0035 0.0030 0.0158*
Weight (kg) 0.0036#−0.0071*0.0210*0.0182*0.0040 −0.006600.0239*0.0193*
Height (cm) 0.0196*0.0459*0.0087*0.0130*0.0210*0.0470*0.0114*0.0113*
TT (nmol/L) 0.0090*0.0092*0.0095*0.0072*0.0103*0.0104#0.0125*0.0088#
ED (vs. non- ED) 0.064000.2659*0.0887*0.1508*−0.10340−0.0208 0.0109 0.0278
Circumcised (vs.
Intercept 4.99 7. 0 4 5.44 5.05 4.88 7. 3 1 4.85 5.39
Adjusted R20.0267 0.0343 0.0506 0.0681 0.0243 0.0423 0.0666 0.0713
Abbreviations: TT, total testosterone; ED, erectile dysfunction.
0p < 0.05.
#p < 0.01.
*p < 0.001.
TABLE 7 Published reports for penile dimensions (pooled data from different countries).
Region Race
Flaccid length (cm) Stretched length (cm)
Mid- shaft
circumference (cm) Glans diameter (cm)
Mean (SD) Study Mean (SD) Study Mean (SD) Study Mean (SD) Study
Western Asia Caucasian 8.96 (1.13) 3 , 1 1 , 2 1 - 2 3 13.21 (1.53) 3,8,11,21- 23,46 8.81 (0.96) 3,8,11 NA
South Asia Caucasian 8.21 (1.44) 47 10.88 (1.42) 47 9.14 (1.02) 47 NA
Europe Caucasian 9.26 (1.77) 7,12,26,48- 5 0 13.51 (2.35) 7, 12 , 26 , 50 10.0 (0.75) 7NA
North America Mixed race 9.01 (2.15) 24, 25 15.52 (2.64) 24,25 9.52 (1.52) 24, 25 NA
East Asia Mongoloid 6.54 (0.73) 15,45,51 12.79 (1.21) 15,45,51 8.01 (0.81) 15 ,51 2.6 (0.3) 15
Vietnam (South-
East Asian)
Mongoloid 9.03 (1.01) 14.67 (1.34) 8.39 (0.92) 2.86 (0.32)
Abbreviations: SD, standard deviation; NA , not available.
reported that, in order to obtain a ratio of erected length to stretched
length that equals to 1, a critical stretching force value of approxi-
mately 450 gram should be applied. 23 However, tension forces while
stretching and measuring penis are usually not stable and are con-
ducted in supine position, which challenges clinicians to perform op-
timal force vector compared with standing position. Consequently,
differences in stretched length among studies could be explained
insufficiently. Although systematic training with consistent proto-
col could reduce the variability of measures, erect penis size should
be studied in the future for indicating the underestimated rate of
stretched length and measuring inter- rater concordance.
Penis grows before birth and during the development of male
body until the end of puberty. Penile development is influenced
by circulating testosterone levels and hormonal activity of the
hypothalamic- pituitary axis.2 8 - 3 0 Therefore, hormonal defects could
be identified as the main cause in a majority of cases of micro-
penis.29 In fact , a general ass essment of endocr ine leve ls is also valu-
able with patient concerned about penis size because of misleading
sexual conception, even when their phallus is normal in length.18 ,19
Micro- penis is widely defined as flaccid length lower than 4.0 cm
and stretched length lower than 7.5 cm.24 In this present study,
any man was diagnosed as having true micro- penis because of pre-
pubertal hypogonadism or developmental abnormalities having
been excluded by previous laboratory tests and physical examina-
tion. However, the size of a penis is not consistent even after full
growth. During adulthood, testosterone still plays a critical role in
the preservation of penile trabecular smooth muscle structure, then
by its turn, maintaining the length and width of the penis.31,32 The
previous experimental studies in castrated animals and observation
in patients with androgen deprivation therapy after prostate cancer
treatments (surgery or radiation) rationally showed reduced penile
length, possibly because of the degeneration of trabecular smooth
muscle content and the change in the structure of extracellular
connective tissue.31- 33 Although this effect could rapidly reverse
after 4 weeks of androgen replacement therapy in sexually mature
adult rats regardless of the androgen deprivation time, the recovery
of penis length in humans after this kind of treatment is not well-
known.33 Even after 6 to 12 months of testosterone therapy to treat
men with late- onset hypogonadism, the stretched penis length was
not significantly changed.34 Moreover, the total testosterone levels
reached during androgen deprivation therapy (<1.7 nmol/L) were
only found in 2 individuals among our 14,597 men.35 Because the
actual influence of testosterone on adult penis size was still contro-
versial, our multivariate linear regression models showed the posi-
tive relations between total testosterone and all penis parameters,
but with no more than 0.2 mm change for every 2 nmol/L increases
in total testosterone. Despite the statistical significance, these
changes were not enough to create a visible difference in the clini-
cal view. Therefore, except for apparent evidence of the continuous
androgen interruption shortening the penile length, the actual role
of testosterone deficiency in penis parameters still needs further
investigation. Radical prostatectomy is another potential factor re-
ported to shorten the adult penile length: however, this is a topic that
is still only partially understood, and complete recovery has been
described after 48 months.36 This could be also because of differ-
ent measurement methods, as starting at the pubo- penile skin angle
might yield different results than starting at the pubic bone.25,36,37
In our protocol, because penile parameters were measured at the
first time of attending before the initial intervention, the effect of
treatments on patients’ penis size was minimized. Furthermore, the
number of patients with a history of radical prostatectomy was min-
imal (34/14,597 men). Thus, our results could be considered as the
reference for normal penis size of Vietnamese men.
While assuming that scar formation after circumcision could
reduce the elasticity of penile skin, especially in the fully stretched
state, the penis shortening complication of circumcision is still not
well- known. However, an observational study in adult men 18 to
28 years old, who had already been circumcised, showed that cir-
cumcision at an earlier age was associated with shorter penile
erected length.38 The flaccid length of the newborn male circum-
cision (NMC) group is even smaller than the non- NMC group. The
present study showed that circumcised men had a significantly re-
duced penis length compared with uncircumcised men; the differ-
ence was only 2 mm, which was possibly not clinically meaningful.
Moreover, differing from the other countries in which circumcision
is obligatory or common for religious and non- religious reasons,
this intervention has not been performed routinely in Vietnam, but
mostly for personal or medical purposes, and with a small prevalence
(5.6% in our study).39
In several papers, correlations between penile dimensions
and somatometric parameters have been investigated; however,
these findings remained questionable. Results from a systematic
rev iew with up to 15,521 mal es in 20 studies showe d that all these
correlations were either inconsistent or weak and the most con-
sistent and strongest significant correlation was between flaccid
stretched length and height.16 Again, our study replicated the
results of relationships found in other studies and demonstrated
weak correlations between penile dimensions and weight, height,
or BMI (with Spearman rho ≤0.200). Furthermore, the size of our
study population could also give greater opportunity to detect
statistical significance even with minor correlations. Interestingly,
BMI was almost non- correlated with penile length (w ith Spearman
rho = 0.046, p < 0.001 for flaccid length and Spearman rho =
−0.022, p < 0.01 for stretched length) when pre- pubic fat pad in-
fluence was eliminated. An increase in fat pad depth might reduce
the visible pendulous length of the penis,24 whi le fun ctio nal le ngth
was not defected. It should be noted that there was a bidirectional
relationship between testosterone levels and obesity40 resulting
in testosterone deficiency, which in its turn might affect the de-
velopment of penis. However, having here a lack of information
regarding the effects of body fat mass during the critical frame
of testosterone action on the penis size, that is, puberty, and the
decrease of penile potential length is a limitation that should be
analyzed by further studies.
To our knowledge, this was one of the first studies that il-
lustrated discrepancies in penile dimensions between men with
different conditions; however, these variances were inconsider-
able. In addition, because of the nature and limitations of non-
parametric test itself, differences in mean between groups might
be misleading. Exceptionally, flaccid length of erectile dysfunction
males was significantly longer than others, especially in cases of
regular reproductive health screening. These results contrasted
with prior studies in which patients with erectile dysfunction have
been found to have significantly shorter penises compared with
normal potent men,10,11 but their data might be limited by the ef-
fect of selective participation that was minimized by our methodol-
ogy. In fact, besides corpus cavernosa and corpus spongiosum, the
role of the tunica albuginea should be taken into consideration in
flaccid penile shape. Tunica albuginea is almost entirely composed
of undulating collagenous bundles connected by elastic fibers.41 It s
branches penetrate the tissue of the corpora cavernosa and act as
an inextensible fibrous frame to support intra- cavernous compo-
nents.42 Patients affected by impotence of all causes showed an
almost complete absence of elastic fibers in tunica albuginea that
produced a stretching of collagen fiber waves.42 Consequently,
these changes slightly lengthened penis in flaccid state in erectile
dysfunction. Treatments are an additional factor possibly affecting
the penile length in patients with erectile dysfunction. Previous
studies have demonstrated that vacuum device can extend length
of th e penis slightly. 43,44 How eve r, in ou r st u d y, all subjec t s ha d their
penis measured at the first time they visited our clinic. Therefore,
patients with erectile dysfunction were either untreated or pre-
scribed with oral pharmacotherapy only because other therapies
such as intra- cavernous injection and vacuum devices had not been
officially approved in Vietnam. Because of minor differences be-
tween each disease groups that could not be clearly interpreted
with current consciousness, further investigation should be per-
formed to confirm these findings.
The present study re- emphasized that penile dimensions did not
follow normal distribution regarding a large sample of men without
factors that could affect penile growth. This hypothesis was men-
tioned in a study of 3,300 young healthy Italian men.7 Ponchietti et al.
suggested that penile length and circumference were characterized
by a high degree of individual variability. Although penile character-
istics were bona fide considered related to paternal impact, the trans-
missions of these phenotypes were still unexplored. In fact, as week
8th of gestation, penis formation and its capacity to grow had been
regulated by fetal androgen action.45 Testosterone action in this state
could be indirectly indicated by digit ratio of right hand correlated
with Homeobox genes (Hox a and d) and androgen receptor (AR) gene
polymorphism.45 However, these findings were not enough to define
penile shape as qualitative phenotypes that basically fell into different
categories with discrete distribution. While waiting for further discov-
ery, normal reference of penile dimensions could be taken impossibly
in either population- based or clinical enrollment with carefully into ac-
count for “normality conditions”.
To date, this was the largest prospective, single center study in
the world for this type of study. However, some limitations should
be mentioned. Although penile measurements were performed as a
part of our physical examination, the participants were not drawn
directly from the population, and as such results of this study might
not represent the general population. Another limitation came from
the number of investigators who directly measured patient's penis,
which was of 5 clinicians. However, experienced andrologists in this
clinic were training under careful observation by the same supervi-
sor with a fixed protocol that might reduce rater errors.
This was the first study establishing reference of penile dimen-
sions for Vietnamese men. These results were valuable for the clini-
cian in practice and might be referred as “normal range” that greatly
assisted in counseling patient. Despite inconsiderable differences
in length and girth of penis between disease groups, these varia-
tions made scientists more aware of micro- changes in penile inner
structure during specific illness, especially with the case of erectile
dysfunction. Finally, because the distributions of penile dimensions
are not normal in nature, sample size might be the main factor that
influenced results of studies on penis size.
Conceptualization: BNH; Data collection: BNH, QPM, TNC; Formal
analysis: AS, EC; Drafting the Article: BNH, AS, EC; Critical revision
and super vision: BNH, EAJ.
Bac Nguyen Hoai
Quan Pham Minh
Thang Nguyen Cao
Andrea Sansone
Emmanuele A. Jannini
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How to cite this article: Nguyen Hoai B, Pham Minh Q,
Nguyen Cao T, Sansone A, Colonnello E, Jannini EA . Data
from 14,597 penile measurements of vietnamese men.
Andrology. 2021;00:1–10. https://doi.o rg /10.1111/
... Several countries have carried out studies on penile size and its correlation with different anthropometric measures. [5][6][7][8][9][10][11][12][13] This is an original study in Argentina. The aim is to inform and adequately advise ORIGINAL ARTICLE Reference penile size measurement and correlation with other anthropometric dimensions: a prospective study in 800 men Trained medical personnel from the Department of Urology of the hospitals cited above obtained prior consent of the patient, various anthropometric measurements, namely height, weight, flaccid penile length, stretched penile length, penile base circumference, and foot length using a centimeter. ...
Full-text available
Virility and sexual pleasure have long been associated with penile size and this, in turn, has typically been linked to some anthropometric measurements, such as foot size or height, leading to various misconceptions from both men and women. Our intention is to estimate penile size parameters in Argentina and evaluate the correlation between penile size and certain anthropometric measurements. This is a cross-sectional, descriptive, multicenter, and observational study. Male patients who underwent a urological procedure were included in four hospitals located in different regions of the country. Different anthropometric measurements were obtained: height, weight, penile circumference, flaccid and stretched length, and foot length. A total of 800 patients were evaluated. Mean left foot was 26.4 cm. Mean flaccid penile length was 11.4 (95% confidence interval [CI]: 8-14) cm, and mean penile circumference was 10.1 (95% CI: 8-12) cm. Finally, mean stretched penis was 15.2 (95% CI: 11-18.5) cm. We can confirm that estimates of the average penile measurements in Argentina are flaccid penis length of 11.4 cm, penile circumference of 10.1 cm, and stretching the penis to the maximum in flaccidity of 15.2 cm. Correlations between flaccid penis length, stretched out, penile circumference, height, weight, and length of the left foot were evaluated, finding low or no correlation between those mentioned, except for flaccid and stretched length.
... Likewise, the impact of concomitant disease on penile dimensions should be noted [6]. For men with a penis of shorter length and dimensions then those of a culturally similar population, the impact on sexual confidence and psychological wellbeing can be considerable. ...
The study by Veale et al. whether artificially reducing the depth of penetration of a penis during intercourse can impact female sexual satisfaction. The researchers used different sizes of silicone rings as a proxy for reducing penis length and report that reducing the depth of penetration led to a statistically significant 18% reduction of overall sexual pleasure following an average 15% reduction in length of the penis. They report that the longer the erect penis the less likely the rings were to have an impact on sexual pleasure.
... With this new technique, Schonfeld and Beebe performed measurements on up to 1,500 patients, from newborns to 25 years of age, establishing the first normative data. SPL is currently the gold standard in any somatometric study [8,9] and its established value of 25 mm (corresponding to 2.5 standard deviations (SD) below the mean) is still used as a cut-off for micropenis at birth [10]. ...
Background Micropenis is an endocrinological condition that is habitually observed at birth. Diagnosis is made by measuring the stretched penile length, a method established 80 years ago. Discrepancies in the normative data from recent studies raise the need for a current revision of the methodology. Objectives The aims of this systematic review were to compare the different normative data of SPL at birth, to examine the methodological aspects of the technique and to evaluate the independent variables that may be involved. Methods Searches were performed using MEDLINE, EMBASE, Scielo, the Cochrane Library and Web of Science. A combination of the relevant medical terms, keywords and word variants for “stretched penile length”, “penile length”, “penile size”, “newborn” and “birth” were used. Eligibility criteria included normative studies that used the stretched penile length (SPL) measurement on a population of healthy, full-term newborns during the first month of life. The outcomes studied included characteristics of the studies, methodological aspects and independent variables. Results We identified 49 studies comprising 21,399 children. Significant discrepancies are observed between the different studies. Methodological aspects seem to be consistent and similar. The main independent variables appear to be ethnic group and gestational age. Main limitations were the absence of studies of entire world regions such as Europe or South America, and the heterogeneity of the ethnic background that complicates the analysis. Conclusions It seems advisable to suggest the creation of customized reference charts for each specific population instead of resorting to the classic cut-off points.
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Purpose: Normative male genital measurements are clinically useful and temporal changes would have important implications. The aim of the present study is to characterize the trend of worldwide penile length over time. Materials and methods: A systematic review and meta-analysis using papers from PubMed, Embase, and Cochrane Library from inception to April 2022 was performed. PRISMA guidelines were used for abstracting data and assessing data quality and validity. Pooled means and standard deviations for flaccid, stretched, and erect length were obtained. Subgroup analyses were performed by looking at differences in the region of origin, population type, and the decade of publication. Metaregression analyses were to adjusted for potential confounders. Results: Seventy-five studies published between 1942 and 2021 were evaluated including data from 55,761 men. The pooled mean length estimates were flaccid length: 8.70 cm (95% CI, 8.16-9.23), stretched length: 12.93 cm (95% CI, 12.48-13.39), and erect length: 13.93 cm (95% CI, 13.20-14.65). All measurements showed variation by geographic region. Erect length increased significantly over time (QM=4.49, df=2, p=0.04) in several regions of the world and across all age groups, while no trends were identified in other penile size measurements. After adjusting for geographic region, subject age, and subject population; erect penile length increased 24% over the past 29 years. Conclusions: The average erect penis length has increased over the past three decades across the world. Given the significant implications, attention to potential causes should be investigated.
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Background Behavioral habits and parental rearing during physical and sexual growth of men can influence to their penis size. Aim To assess the erect penis size in adult Kazakh males and study the influence of their physiological events and behavioral habits during their body growth on their penis size. Methods A cross-sectional survey pilot study with the intention-to-treat. The study included 282 adult Kazakh fertility males aged 23-35 years. Interventions: paper-based survey administration; erect penis length and girth measurement. Two-tailed Student’s t-test, Pearson correlation, and multivariate tests of the MANOVA/MANCOVA were used. The Ethics Committee of the National Research oncology center approved the study. Outcomes In Kazakh men a mean age 29.6±4.4 years; body height 171.56±6.64 cm; BMI 24.53±3.40 kg/m²; erect penis length 13.41±1.04 cm and girth 11.62±0.91 cm. Results There was a significant correlation between erect penis length and girth (P<0.0001). The frequency of erection in 54.7% males was 5-6 times a day. The frequency of masturbation or coitus with ejaculation in 42.2% males was two times per month. 40.9% males abstained to masturbation or coitus in one of two cases. The frequency of nocturnal sperm emission was in 39.1% males one time per month. Frequencies of erection, masturbation/coitus, abstinence to masturbation/coitus, and nocturnal emission have a statistically significant effect (P<0.01) on both erect penis length and girth in Kazakh males in their body growth. Conclusions Sexual abstinence to coitus and masturbation during childhood has a positive increasing affect on the penis size in adulthood. The more males in childhood abstains from ejaculation, the larger their penis size in adulthood. A long-lasting extended erection during body growth has a positive effect on penis enlargement.
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Testicular size is an important parameter to investigate male reproductive and sexual functions. However, diagnosis and treatments are hindered by the lack of country-specific standard values for testicular volume. We conducted the present retrospective chart review study on 24,440 men who sought consultation at Andrology and Sexual Medicine—Hanoi Medical University Hospital to provide a reference range of testicular volume and to determine the correlations between testicular volume, age and hormonal profiles. These men were classified into groups being healthy fathers, hypogonadal men, unexplained infertile men, men with unknown fertility, testicular pathologies and other andrological condition groups. Hypogonadal men and unexplained infertile men had significantly smaller testicular sizes compared with healthy fathers. The mean value of testicular volume of healthy subjects was 13.64 ± 3.44 ml (left testis: 13.94 ± 3.72 ml; right testis: 13.34 ± 3.61 ml; p < 0.001). Testicular size of Vietnamese men was negatively correlated with LH and FSH (Rho = −0.16 and −0.33, p < 0.001) and positively correlated with testosterone after adjusting for confounding factors. Testicular volume was independent of the subject's age and smoking habits.
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Introduction The “lost penis syndrome” (LPS) is a term often used in non-clinical settings to describe the subjective perception of the loss of cutaneous and proprioceptive feelings of the male organ during vaginal penetration. Although deserving clinical attention, this syndrome did not receive any consideration in the medical literature. Notwithstanding, it represents a relatively unexceptional condition among patients in sexual medicine clinics, and it is often reported together with other sexual dysfunctions, especially delayed ejaculation, anejaculation, male anorgasmia and inability to maintain a full erection. Objectives To draft a new conceptual characterization of the LPS, defined as a lack of penile somesthetic sensations during sexual penetration due to various causes and leading to several sexual consequences in both partners. Methods Based on an extensive literature review and physiological assumptions, the mechanisms contributing to friction during penovaginal intercourse, and their correlation to LPS, have been explored, as well as other nonanatomical factors possibly contributing to the loss of penile sensations. Results Efficient penile erection and sensitivity, optimal vaginal lubrication and trophism contribute to penovaginal friction. Whenever one of these processes does not occur, loss of penile sensation defined as LPS can occur. Sociocultural, psychopathological and age-related (ie, couplepause) factors are also implicated in the etiology. Four types of LPS emerged from the literature review: anatomical and/or functional, behavioral, psychopathological and iatrogenic. According to the subtype, a wide variety of treatments can be employed, including PDE5i, testosterone replacement therapy and vaginal cosmetic surgery, as well as targeted therapy for concomitant sexual comorbidity. Conclusion We held up the mirror on LPS as a clinically existing multifactorial entity and provided medical features and hypotheses contributing to or causing the occurrence of LPS. In the light of a sociocultural and scientific perspective, we proposed a description and categorization of this syndrome hypothesizing its usefulness in daily clinical practice. Colonnello E, Limoncin E, Ciocca G, et al. The Lost Penis Syndrome: A New Clinical Entity in Sexual Medicine. Sex Med Rev 2021;XX:XXX–XXX.
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The aim of the present study was to evaluate the size of the penis in flaccidity and in erection of Italian men. A total of 4,685 men living in Italy and who have been visited at the Italian urology operating units were involved in the study between January 2019 and January 2020. Each patient was given details on how to measure their penis (erect length and circumference) in flaccidity and in erection, from the lower base to the distal penile tip. Mean (standard deviation [SD]) flaccid penis length was 9.47 (2.69), mean (SD) flaccid penis circumference was 9.59 (3.08), mean (SD) erect penis length was 16.78 (2.55) and mean (SD) erect penis circumference was 12.03 (3.82). At the linear regression analysis, height was associated with flaccid penis length (β = 0.04; p‐value = .01), and erect penis length was (β = 0.05; p‐value < .01) and erect penis circumference was (β = 0.06; p‐value < .01). Height is proportional to the length of the penis in flaccidity and in erection, and to the circumference in erection. The increase in BMI leads to a reduction in the length of the erect penis, as well as weight gain reduces the length of the flaccid penis.
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Objective: This study aimed to evaluate the relationship between penile morphometrics and erectile function in a sample of healthy Portuguese men. Methods: A sample of 1416 adult men with an average age of 39 years were surveyed and completed the following measures: socio-demographic questionnaire, penile morphometrics evaluation questionnaire, and the Portuguese version of the International Index of Erectile Function-5 (IIEF-5). Results: The average result for penis length was 16.75 cm (SD=2.25) and a circumference of 9.56 cm (SD=2.38). Levels of satisfaction with the morphometrics of the penis were relatively high (7.61 on a scale of 1 to 10, SD=1.87), as well as overall levels of erectile function (4.21 on a scale of 1 to 5; SD=0.61). Results showed a negative association between penis length and erectile function (r=-242; p<0.05), and positive association between the circumference and erectile function (r=0.183; p<0.05); penile length and circumcision was associated with less erectile function. Conclusion: This study provides evidence that penile morphometrics interferes with erectile function and this is an important source of information for professionals working in the male sexual health field.
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Previous studies demonstrate that many men have insecurities about the size of their penises, often resulting in low sexual self-esteem and sexual problems. In the present study, mean self-reported erect penis length by 130 sexually experienced college men (6.62 inches) was greater than found in previous studies in which researchers took measurements. This suggests that many of the men embellished their responses. Only 26.9% of the sexually experienced men self-reported penis lengths of less than 6 inches, while 30.8% self-reported lengths of 7 inches or more (with 10% self-reporting 8 inches or more). The correlation with Marlowe–Crowne social desirability scores was +.257 (p < .01), indicating that men with a high level of social desirability were more likely than others to self-report having a large penis.
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In colloquial English, a “grower” is a man whose phallus expands significantly in length from the flaccid to the erect state; a “shower” is a man whose phallus does not demonstrate such expansion. We sought to investigate various factors that might predict a man being either a grower or a shower. A retrospective review of 274 patients who underwent penile duplex Doppler ultrasound (PDDU) for erectile dysfunction between 2011 and 2013 was performed. Penile length was measured, both in the flaccid state prior to intracavernosal injection (ICI) of a vasodilating agent (prostaglandin E1), and at peak erection during PDDU. The collected data included patient demographics, vascular, and anatomic parameters. The median change in penile length from flaccid to erect state was 4.0 cm (1.0–7.0), and was used as a cut-off value defining a grower (≥4.0 cm) or a shower (4.0 cm). A total of 73 men (26%) fit the definition of a grower (mean change in length of 5.3 cm [SD 0.5]) and 205 (74%) were showers (mean change in length of 3.1 cm [SD 0.9]). There were no differences between the groups with regards to race, smoking history, co-morbidities, erectile function, flaccid penile length, degree of penile rigidity after ICI, or PDDU findings. Growers were significantly younger (mean age 47.5 vs. 55.9 years, p < 0.001), single (37% vs. 23%, p = 0.031), received less vasodilator dose (10.3 mcg vs. 11.0 mcg, p = 0.038) and had a larger erect phallus (15.5 cm vs. 13.1 cm, p < 0.001). On multivariate analysis, only younger age was significantly predictive of being a grower (p < 0.001). These results suggest that younger age and single status could be predictors of a man being a grower, rather than a shower. Larger, multicultural and multinational studies are needed to confirm these results.
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Genital size is a crucial index for the assessment of male sexual development, as abnormal penile or testicular size may be the earliest visible clinical manifestation of some diseases. However, there is a lack of data regarding penile and testicular size measurements for Chinese boys at all stages of childhood and puberty. This cross-sectional study aimed to develop appropriate growth curves and charts for male external genitalia among children and adolescents aged 0-17 years in Chongqing, China. A total of 2974 boys were enrolled in the present study. Penile length was measured using a rigid ruler, penile diameter was measured using a pachymeter, and testicular volume was determined using a Prader orchidometer. Age-specific percentile curves for penile length, penile diameter, and testicular volume were drawn using the generalized additive models for location, scale, and shape. Very similar growth curves were found for both penile length and penile diameter. Both of them gradually rose to 10 years of age and then sharply increased from 11 to 15 years of age. However, testicular volume changed little before the age of 10 years. This study contributes to the literature covering age-specific growth curve and charts about male external genitalia in Chinese children and adolescents. These age-related values are valuable in evaluating the growth and development status of male external genitalia and could be helpful in diagnosing genital disorders.
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Short periods of testosterone suppression have been shown to reduce trabecular smooth muscle content and increase interstitial connective tissue accumulation in animal models. However, the long-term effects of testosterone suppression remain unclear. The aim of this study was to evaluate the long-term effects of testosterone suppression on penile structure and erectile function in rats. Subjects were divided into two groups by observation period (short-period group (group I), 12 weeks; long-period group (group II), 20 weeks). Each group comprised three different subgroups (10 rats each): sham-operated control, surgical castration, and testosterone replacement (4 weeks after an 8-week castration period). Group II subgroups included a sham control, surgical castration, and testosterone replacement (4 weeks after a 16-week castration period). Erectile function was assessed by measuring intracavernosal pressure in response to cavernous nerve stimulation, and expression of the endothelial nitric oxide synthase (eNOS) protein was determined by western blot analysis. Serum testosterone values were measured via radioimmunoassay. The results indicated that serum testosterone level, penile length and girth, cavernosal smooth muscle content, and eNOS activity decreased significantly in castrated animals. These effects were rescued by testosterone undecanoate injection. Erectile function was normalized over 4 weeks in rats that received androgen replacement. Expression of eNOS was decreased in the corpus cavernosum of castrated animals compared with controls, while androgen replacement normalized the expression of eNOS. These results were consistently observed regardless of the duration of androgen deprivation. Thus, these data suggest that androgen regulates the expression of eNOS in the rat penile corpus cavernosum and confirm the importance of androgens in the maintenance of erectile function. Additionally, long-term androgen deprivation does not induce irreversible structural or erectile functional changes in sexually mature adult male rats.
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Background: Late-onset hypogonadism (LOH) presents with low serum testosterone (TT) levels and sexual and nonsexual symptoms. Erectile dysfunction affects a man’s self-esteem and as a result partner relationship and quality of life. Objectives: To investigate the andrological clinical profile outcomes of testosterone therapy (TTh) in men (n = 88) with symptomatic LOH complaints and symptoms. Main outcome measures: Erectile function was assessed using the International Index of Erectile Function-5 questionnaire at baseline and at 6 and 12 months of TTh. In addition, penile length was measured at baseline and 12 months. We also evaluated nocturnal penile tumescence (NPT, using RigiScan) and blood flow of cavernous arteries (penile Doppler ultrasonography) at baseline and 12 months of TT. Materials and methods: Eighty-eight LOH men (Mage 51.1 years) with erectile dysfunction, all with serum TT <10.4 nmol/L before TTh. Patients received intramuscular long-acting testosterone undecanoate for 12 months. Results: Following TTh, in all patients, serum TT levels were restored within 3 months to normal levels. Compared with baseline values, erectile function significantly improved at 6 (mean score increase 1.95) and 12 months (mean score increase 2.16). No significant changes in penile length were observed. NPT significantly improved at 12 months in terms of both the frequency (mean increase 1.27 times) and duration of rigidity (mean increase 5.12 min). As regards the blood flow of the cavernous arteries, we observed a significant improvement (decrease of 1.16 cm/s) and end diastolic velocity of the penile arteries. Conclusion: TTh in men with LOH resulted in improvement of the erectile function, NPT, and to some extent the blood flow of the cavernous arteries.
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Male genital satisfaction is an important aspect of psychosocial and sexual health. The Index of Male Genital Image (IMGI) is a new scale that measures perceptions of male genitalia. We aim to characterize genital satisfaction using the IMGI and correlate dissatisfaction with sexual activity. We conducted a nationally representative survey of non-institutionalized adults aged 18–65 years residing in the U.S. In total, 4198 men completed the survey and 3996 (95.2 %) completed the IMGI. Men reported highest satisfaction with the shape of their glans (64 %), lowest satisfaction with the length of their flaccid penis size (27 %), and neutrality with the scent of their genitals (44 %). No demographic characteristics (age, race, sexual orientation, education, location, and income) were significantly associated with genital dissatisfaction. Men who were dissatisfied with their genitals were less likely to report being sexually active (73.5 %) than those who were satisfied (86.3 %). Penetrative vaginal sex (85.2 vs. 89.5 %) and receptive oral intercourse (61.0 vs. 66.2 %) were reported less by dissatisfied men. Overall, most U.S. men were satisfied with their genitals; however, a subset (14 %) report low genital satisfaction, which included men of all ages, races, and socioeconomic groups. Low genital satisfaction is associated with a decrease in sexual activity. These results provide clinicians and health educators a baseline of genital satisfaction to provide education and reassurance.
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p> Introduction: We prospectively investigated the relationship between newborn male circumcision (NMC) and second to fourth digit ratio with penile length. Methods: As participants for our study, we identified already circumcised young patients who visited our hospital for urological treatment. The age at which the circumcision had been done was assessed. The patients’ height and weight were measured. Second to fourth digit ratio was calculated by measuring the second and fourth digit lengths. The flaccid and erectile penile lengths were measured from the base of the penis to the tip of the glans in standing position. Results: A total of 248 patients were included in our study. In univariate analysis, height, second to fourth digit ratio, flaccid penile length, and age of circumcision were associated with erectile penile length. Among these variables, second to fourth digit ratio, flaccid penile length, and age of circumcision were significant predictive factors for erectile penile length in multivariate analysis. The subjects were divided into two groups, including 72 patients in the NMC group and 176 patients in the non-NMC group. No significant difference was found in height, weight, and second to fourth digit ratio between both groups. However, flaccid (p<0.001) and erectile (p=0.001) penile lengths were shorter in the NMC group than in the non-NMC group. Conclusions: Despite the small number of subjects, this study shows that NMC was associated with shorter penile length. Second to fourth digit ratio, flaccid penile length, and age of circumcision were also significant predictive factors for erectile penile length. Further multicentre studies with larger number of subjects and biochemical analyses are needed for potential clinical applicability</p
Introduction: Peyronie's disease (PD) has historically been managed by at least 1 treatment, including oral supplements or medications, intralesional injections, or surgery. Adjunctive mechanical therapies also have been described, including penile traction therapy (PTT) and vacuum erection devices (VEDs), although relatively limited data are available on their use with PD. Aim: To review and summarize the published literature on the role and efficacy of PTT and VED in men with PD. Methods: A PubMed search was performed of all publications on PTT and VED in men with PD from inception through September 2017. Main outcome measures: Changes in penile curvature, length, girth, erectile function, and adverse events with PTT or VED. Results: PTT and VED exhibit mechanisms to improve aspects of PD, although clinical outcomes data are limited. Based on current data, PTT likely has a potential role as a primary lengthening therapy (modest improvements), in curvature correction (acute phase; unclear role in chronic phase), before penile prosthesis insertion, and after surgical correction of PD. The role of PTT as a combination therapy during collagenase Clostridium histolyticum injections is unclear. Fewer and lower level-of-evidence studies are available on VEDs and suggest potential roles in curvature correction, before penile prosthesis placement, or after PD surgery. Guideline statements from the American Urological Association and International Consultation on Sexual Medicine also support the potential role of PTT and VED in managing PD. Conclusions: PTT and VED represent viable therapeutic options for managing PD, with more data currently available on PTT. Because all PTT studies used a similar style of traction device, it is unclear whether results reflect outcomes of these particular devices or traction more broadly. Further studies are required to better delineate the benefits of PTT and VED, particularly in relation to other established treatments. Avant RA, Ziegelman M, Nehra A, et al. Penile Traction Therapy and Vacuum Erection Devices in Peyronie's Disease. Sex Med Rev 2018;X:XXX-XXX.