Background: Universal reference values of penile length, circumferences and testicular
volume in newborns and infants are inappropriate to be used in variable ethnic backgrounds.
Objective: The aim of this prospective study was to establish normal reference values for stretched
penile length, penile circumference and testicular volume for Egyptian newborn and infants.
Subjects and Methods: This observational cross-sectional study included 1850 healthy male full term
newborn and infants applied for routine check-up, aged 0 -24 months, the newborn and infants were
recruited from Tanta University Hospital in the period from July 2015 to January 2017. Penile length,
penile circumference, testicular volume, weight, length and occipito-frontal circumference were measured.
Results: The studied infants were divided into five groups. Group I: 1-4 weeks, the mean penile length
was 3.51 ± 0.49 cm, penile circumference was 3.95 ± 0.48 cm, and testicular size was (right 1.81 ±
0.44 cm and left 1.67 ± 0.47 cm). Group II: > 1-6 months age, the mean penile length was 3.99 ± 0.46
cm, penile circumference was 4.10 ± 0.38 cm, and testicular size was (right 2.10 ± 0.33 cm and left
2.04 ± 0.27 cm). Group III: >6-12 months age, the mean penile length was 4.45 ± 0.48 cm, penile circumference
was 4.21 ± 0.33 cm, and testicular size was (right 2.13 ± 0.33 cm and left 2.06 ± 0.28 cm).
Group IV: >12-18 months age, the mean penile length was 4.55 ± 0.54 cm, penile circumference was
4.28 ± 0.32 cm, and testicular size was (right 2.12 ± 0.33 cm and left 2.09 ± 0.32 cm). Group V: >18-24
months age, the mean penile length was 4.89 ± 0.63 cm, penile circumference was 4.45 ± 0.33 cm, and
testicular size was (right 2.28 ± 0.45 cm and left 2.25 ± 0.45 cm). There were significant positive correlations
between penile length, penile circumference, left and right testicular volumes with each other and
also with all other anthropometric measures including: weight, height and head circumference.
Conclusion and Recommendation: The age-related values of penile and testicular measurements must
be known to be able to determine the abnormal sizes and to monitor treatment of underlying diseases.
Our study is a step to achieve accurate reference values of penile and testicular measurements for
Egyptian male newborns and infants. Therefore multicenter studies are recommended to establish