Testicle fetal abdomen to the inguinal ring and beyond to the inguinal canal and into the scrotum. In most cases (97% full-term, 70% preterm), both testes have descended by birth. In most other cases, only one testis fails to descend (cryptorchidism) and that will probably express itself within a year. The testes grow in response to the start of spermatogenesis. Size depends on lytic function, sperm production (amount of spermatogenesis present in testis), interstitial fluid, and Sertoli cell fluid production. After puberty, the volume of the testes can be increased by over 500% as compared to the pre-pubertal size. Testicles are
Users' Guides to the Medical Literature to the medical literature, II: how to use an article about therapy or prevention, A: are the results of the study valid? JAMA, 270, pp. 2598–2601. Guyatt, G., Sackett, D. & Cook, D., 1994. Users’ guides to the medical literature, II: how to use an article about therapy or prevention, B: what were the results and will they help me in caring for my patients? JAMA, 271, pp. 59–63. Guyatt, G.H. & Rennie, D., 1993. Users’ guides to the medical literature. JAMA, 270(17), pp. 2096–2097. Available at: http://jama.ama-assn.org. Guyatt, G.H. et al., 2000. Users’ Guides to the Medical Literature: XXV.