The Descent of the Testis

Abstract

This study is based on observations made on boys at birth, during infancy, and throughout early childhood. Its purpose was to find out how often the testes were in the scrotum at birth and what happened in later years to those that were not.An analysis of the position of the testes was made in over 3,500 infant boys at birth. Those in whom one or both testes were not in the scrotum at the age of 1 month were followed up. To this number a further 40 cases of failure of descent in early infancy have been added in order to obtain, as nearly as possible, a true incidence of the various types of failure.

Temporal trends in orchidopexy, Great Britain, 1992-1998.

“…Reported worldwide incidence of undescended testis varies considerably as a result of differing study populations and diagnostic criteria (Toppari and Kaleva 1999), although introduction of a standardized definition of maldescent (Scorer 1964), reproduced in large cohort studies (Berkowitz et al 1993;John Radcliffe Hospital Cryptorchidism Study Group 1986, 1992, has enabled meaningful comparisons. In London in the late 1950s, the prevalence of cryptorchidism was just under 1% at 3 months (Scorer 1964), but by the late 1980s in an Oxford study it was 1.8% (John Radcliffe Hospital Cryptorchidism Study Group 1992).…”

Cryptorchidism: Treatment with Human Chorionic Gonadotropin—a Venezuelan Experience

“…In the 1950s, Scorer [39] reported an overall incidence of cryptorchidism of 2.7% at birth and 0.9% at 3 months in term male neonates. In the same study, low birth weight was pointed to as a risk factor for testicular maldescent.…”

Clinical diagnosis of cryptorchidism. John Radcliffe Hospital Cryptorchidism Study Group

“…This classification forms the basis of our definition of 'undescended Table 2 shows the number of boys cryptorchid at 3 months and the number cryptorchid at birth cross classified by the measurement and position of the boy's worst testis at birth. All testes 4 cm or more from the pubic tubercle (or 2-5 cm or more for babies weighing less than 2500 g) descended spontaneously by 3 For a given position of the testis, babies weighing less than 2500 g appear to have a greater chance of spontaneous descent than larger babies (with the exception of the anomalous figure of six out of 51 for the larger babies with a suprascrotal testis that appears to be much too low). Table 3 shows the number of boys cryptorchid at 3 months and the number cryptorchid at birth (by position) cross classified by gestational age and the position of the worst testis at birth.…”

“…Measurement was made after manipulation of the testis into the lowest position along the pathway of normal anatomical descent without tension being applied. This definition of undescended testis is precisely that adopted by Scorer,3 Group and, for the purposes of this paper defines 'undescended testis by measurement.' In addition to recording these measurements of the testes, the position of each testis was classified as follows: normal (well down in the scrotum), high scrotal, suprascrotal (palpable, in the line of normal descent including the inguinal pouch, but not in the scrotum), non-palpable, and 'other'-ectopic (three), neonatal orchidopexy before examination (one), and position obscured by hernia or hydrocoele (two).…”

“…Moreover, Scorer's data had suggested previously that most late descending testes do, in fact, descend before 3 months of age. 3 The rationale for examination at three months after the expected date of delivery in premature infants is that these infants have a very high rate of cryptorchidism but many of the testes descend spontaneously. Although Scorer does not suggest that cryptorchid testes in premature babies descend after the third month,3 his data are not strictly applicable to our series as very premature babies are now much more likely to survive.…”