Palpation and inspection of the testes facilitates an approximation of testicular volume by comparing it to the beads on the orchidometer. Links: Endocrinology - Precocious sexual development | NICHD - Precocious Puberty | Nemours Foundation - Precocious Puberty | MedlinePlus - Obesity May Trigger Earlier Puberty for Girls | Time Magazine - Teens Before Their Time | Delayed Puberty Griswold MD. The central role of Sertoli cells in spermatogenesis. Semin Cell Dev Biol. 1998;9(4):411-416. doi:10.1006/scdb.1998.0203

These papers originally appeared in the Some Recent Findings table, but as that list grew in length have now been shuffled down to this collapsible table.The orchidometer consists of a series of 12 graduated beads that range in size from 1 to 25 milliliters (ml). Testicular volume assessment using an orchidometer allows objective measurement of testicular size. The beads are graded by volume, starting at 1 to 3ml for prepubertal testicles, 4 to 12 ml for puberty, and 15 to 25ml for adult-sized testicles. The links below are to general public external text resources (this listing is for information purposes only and is not intended as an endorsement of a commercial product). Dungan HM, Clifton DK & Steiner RA. (2006). Minireview: kisspeptin neurons as central processors in the regulation of gonadotropin-releasing hormone secretion. Endocrinology , 147, 1154-8. PMID: 16373418 DOI.

The orchidometer was introduced in 1966 by Swiss pediatric endocrinologist Andrea Prader of the University of Zurich. [1] It consists of a string of twelve numbered wooden or plastic beads of increasing size from about 1 to 25 millilitres. Doctors sometimes informally refer to them as "Prader's balls", "the medical worry beads", or the "endocrine rosary". [2] https://maleinfertility.org/understanding-male-infertility/anatomy-physiology-male-reproduction/testicular-anatomy These notes cover normal postnatal development during the puberty period which occurs mainly in the early teenage years. Triggers to puberty include neuroendocrine changes in hypothalamic expression of kisspeptin which is suggested in turn to change gonadotropin releasing hormone (GnRH) levels. (More? Kisspptin | Gonadotropin Releasing Hormone | Endocrine Notes - Hypothalamus) An undescended testicle. Your testicle may not have developed fully because it didn’t descend correctly in childhood.Klinefelter Syndrome. An extra copy of the X chromosome will result in smaller testicles (usually up to 6 ml). If only a part of your cells have an extra X chromosome, you may suffer from mosaic Klinefelter Syndrome. Your testicles may be 6-15 ml in size. Use the orchidometer app to find out if it could be Klinefelter Syndrome. The beads are compared with the testicles of the patient and the volume is read off the bead which matches most closely in size. The scale is as follows:

small amount of long, downy hair with slight pigmentation at the base of the penis and scrotum (males) or on the labia majora (females) Khadilkar VV, Khadilkar AV, Kinare AS, Tapasvi HS, Deshpande SS & Maskati GB. (2006). Ovarian and uterine ultrasonography in healthy girls between birth to 18 years. Indian Pediatr , 43, 625-30. PMID: 16891683 The Prader Orchidometer is an instrument used to measure the volume of the testicles. It consists of a chain of 12 numbered beads of increasing size: 1ml to 25 ml. Discrepancy of testicular size with other parameters of maturation can be an important clue to various diseases. https://www.researchgate.net/publication/261063774_The_relationship_between_testosterone_concentration_sperm_count_and_motility_in_fertile_Nigerian_males Stocco C. Tissue Physiology and Pathology of Aromatase. Steroids. 2012;77(1-2):27-35. doi:10.1016/j.steroids.2011.10.013Lee HK, Choi SH, Fan D, Jang KM, Kim MS & Hwang CJ. (2018). Evaluation of characteristics of the craniofacial complex and dental maturity in girls with central precocious puberty. Angle Orthod , 88, 582-589. PMID: 29708396 DOI. It’s often used to help women who are having difficulty becoming pregnant, but it can be used to treat male infertility, too. Hypogonadism is a condition in which the body doesn’t produce enough testosterone to help ensure proper development of male characteristics, such as the penis, testicles, and muscle mass. Primary hypogonadism An orchidometer (or orchiometer) is a medical instrument used to measure the volume of the testicles. Disclaimer: I am not a doctor and I cannot give any medical advice. Always consult with a doctor if you want a correct medical diagnosis. Reply