The frequency of undescended testis from birth to adulthood: a review

Abstract

We performed a systematic review and critique of the literature on the frequency of undescended testis (UDT) among boys from birth to adolescence. Special attention was given to whether previous testicular position was taken into account to distinguish between congenital and acquired UDT. We searched Medline, Embase, Cinahl and the Cochrane Library. Any study reporting on the frequency of UDT was included. Study population age, number of boys studied, period of examination, primary examiner, area of study, study design, ethnicity, definitions used and previous testicular position were analysed. A total of 46 studies met the inclusion criteria. Twenty-three of the 46 (50%) studies involved newborns. Definitions were described in half of the studies; however, the definitions used were heterogeneous. Previous testis position was described in 11% (5/46) of the studies. At birth, in term and/or birth weight >2.5 kg infants, the UDT rate ranged from 1.0 to 4.6%, and in premature and/or birth weight <2.5 kg infants from 1.1 to 45.3%. At the age of 1 year UDT in term and/or birth weight >2.5 kg infants was seen in 1.0-1.5%, at 6 years in 0.0-2.6%, at 11 years in 0.0-6.6% and at 15 years in 1.6-2.2% of boys. The frequency of UDT shows variable figures in the literature. The actual frequency of acquired UDT essentially remains unclear because of the shortage of studies performed at an older age, and of studies reporting on previous testicular position.

Canadian Urological Association-Pediatric Urologists of Canada (CUA-PUC) guideline for the diagnosis, management, and followup of cryptorchidism

“…Cryptorchidism is diagnosed in 1.0-4.6% of full-term and 1.1-45.3% of preterm male neonates. 1 In up to one-third of cases, the condition may affect both gonads. 2 Following spontaneous decent, often seen in the first 3-6 months of life, prevalence stabilizes at 0.7-1.0% of one-year-old boys.…”

Role of Imaging in the Evaluation of Non-Palpable Testes: A Rare Case of Ectopic and Undescended Testes in an Adult

“…It is the most common congenital genitourinary anomaly in boys and has an incidence of 1-3% in term and 15-30% in premature male infants. [12] The etiology of cryptorchidism is not well understood. The undescended testicles may be palpable or nonpalpable, approximately 20% of undescended testes are non-palpable and either located in the abdomen or the canaliculi, or atrophic or are completely absent.…”

Criptorquidia: desde la embriología al tratamiento

“…Algunos autores utilizan el término criptorquidia exclusivamente para referirse al descenso incompleto del testículo, con ubicación dentro del trayecto normal hacia el escroto y distinguen a la ectopia testicular y al testículo retráctil (Ver Figura 1) 1,2 . La evaluación y el tratamiento de la criptorquidia han progresado durante décadas pasadas.…”

“…De acuerdo a diferentes estudios publicados se ha encontrado que la criptorquidia afecta entre 1,6% y 5,7% de los recién nacidos a término 1,4 , con una incidencia mayor del 30 a 40% en recién nacidos pretérmino 2,5 . Los testículos pueden descender al escroto espontáneamente durante el primer año de vida, generalmente en los tres primeros meses de vida en el 75% de los recién nacidos a término y en el 90% de los recién nacidos prematuros; así, la prevalencia de criptorquidia disminuye entre 0,8% y 1,2% en el primer año de vida.…”