Editing Testicle (section)

===Measurement and volume===
The volume of the testicle can be estimated by palpating it and comparing it to [[ellipsoid]]s (an [[orchidometer]]) of known sizes. Another method is to use calipers, a ruler, or an [[ultrasound]] image to obtain the three measurements of the x, y, and z axes (length, depth and width). These measurements can then be used to calculate the volume, using the formula for the volume of an ellipsoid: 
:<math>Volume = \frac{4}{3} \cdot \pi \cdot \frac{length}{2} \cdot \frac{width}{2} \cdot \frac{depth}{2}</math>
:<math>\approx length \cdot width \cdot depth \cdot 0.52</math>

However, the most accurate calculation of actual testicular volume is gained from the formula:<ref name="Lao">{{Cite book|last1=Lao|first1=Michael|last2=Smith|first2=Shannon|last3=Gilbert|first3=Bruce R.|title=Practical Urological Ultrasound|chapter=Male Reproductive Ultrasound|chapter-url=https://books.google.com/books?id=QU8AEAAAQBAJ&pg=PA298|date=2020|publisher=Springer Nature|isbn=978-3-03-052309-1|page=298|access-date=2022-07-05|archive-date=2023-06-29|archive-url=https://web.archive.org/web/20230629155354/https://books.google.com/books?id=QU8AEAAAQBAJ&pg=PA298|url-status=live}}</ref>

:<math>\approx length \cdot width \cdot depth \cdot 0.71</math>

An average adult testicle measures up to {{convert|5|×|2|×|3|cm|in|frac=4|abbr=on}}. The [[Tanner scale#Genitals (male)|Tanner scale]], which is used to assess the maturity of the male genitalia, assigns a maturity stage to the calculated volume ranging from stage I, a volume of less than 1.5&nbsp;cm<sup>3</sup>; to stage V, a volume greater than 20&nbsp;cm<sup>3</sup>. Normal volume is 15 to 25&nbsp;cm<sup>3</sup>; the average is 18&nbsp;cm<sup>3</sup> per testis (range 12–30&nbsp;cm<sup>3</sup>).<ref name="Steger"/>

The number of spermatozoa an adult human male produces is directly proportional to testicular volume, as larger testicles contain more seminiferous tubules and [[Sertoli cells]] as a result.<ref name="Rhoades">{{Cite book|last1=Rhoades|first1=Rodney A.|last2=Bell|first2=David R.|title=Medical Physiology: Principles for Clinical Medicine|date=2012|publisher=Lippincott Williams & Wilkins|isbn=978-1-60-913427-3|page=681|url=https://books.google.com/books?id=1kGcFOKCUzkC&pg=PA681|access-date=2022-07-05|archive-date=2023-06-29|archive-url=https://web.archive.org/web/20230629155405/https://books.google.com/books?id=1kGcFOKCUzkC&pg=PA681|url-status=live}}</ref> As such, men with larger testicles produce on average more sperm cells in each [[ejaculate]], as testicular volume is positively correlated with semen profiles.<ref>{{cite journal | doi=10.1155/2013/145792 | doi-access=free | title=Relationship between Testicular Volume and Conventional or Nonconventional Sperm Parameters | year=2013 | last1=Condorelli | first1=Rosita | last2=Calogero | first2=Aldo E. | last3=La Vignera | first3=Sandro | journal=International Journal of Endocrinology | volume=2013 | pages=1–6 | pmid=24089610 | pmc=3780703 }}</ref>