Cryptorchidism — failure of one or both testes to reach the scrotum — is the most common urogenital anomaly of newborn boys. The testes develop intra-abdominally and normally descend through the inguinal canal into the scrotum in late gestation; interruption of this descent leaves the testis in the inguinal canal or abdomen.

The condition affects approximately 1.0-4.6% of full-term male neonates and up to 45% of preterm infants.

Spontaneous Descent: What Can Be Expected?

A substantial proportion of testes undescended at birth complete their descent spontaneously during the first months of life, under the influence of the postnatal hormonal surge, predominantly within the first 3-6 months.

Beyond six months of age, spontaneous descent becomes rare, and by one year of age cryptorchidism persists in approximately 1% of boys.

Accordingly, an undescended testis identified at birth is followed with serial examination during early infancy; if the testis remains undescended at six months, treatment planning should begin rather than continued observation.

Why Timely Treatment Matters

• Fertility: scrotal temperature is several degrees below core body temperature, and normal germ cell maturation depends on this cooler environment. Histological studies demonstrate progressive loss of germ cells and Leydig cells in undescended testes beginning within the first year of life — the biological rationale for early surgery.
• Malignancy: men with a history of cryptorchidism carry a severalfold increased relative risk of testicular cancer. Prepubertal orchidopexy significantly attenuates this risk: in a large Swedish cohort (Pettersson et al., NEJM 2007), the relative risk was 2.23 when surgery was performed before age 13, versus 5.40 with later treatment. A scrotal testis is also accessible to palpation, facilitating early detection in adulthood.
• Associated pathology: a patent processus vaginalis (inguinal hernia) frequently accompanies cryptorchidism and is repaired during the same operation; the risk of testicular torsion is also increased in undescended testes.
• Psychological and cosmetic considerations: scrotal symmetry is relevant to body image in later childhood and adolescence.

Diagnosis: Clinical Examination Is the Standard

Routine imaging is not recommended

The diagnosis of cryptorchidism is established by physical examination performed by an experienced clinician in a warm, calm setting.

A frequently asked question deserves a clear answer: international guidelines (EAU/ESPU and AUA) do not recommend ultrasound or MRI for localizing the testis, as imaging neither reliably adds to expert examination nor alters management.

For the non-palpable testis, diagnostic laparoscopy is the gold standard, offering simultaneous diagnosis and treatment. Bilaterally non-palpable testes in a newborn require an urgent endocrinological and genetic work-up to exclude disorders of sex development.

The Retractile Testis Is a Distinct Entity

In some boys an overactive cremasteric reflex intermittently draws the testis toward the groin, yet on examination the testis can be brought comfortably into the scrotum and remains there.

This retractile testis does not require surgery; however, because a minority later ascend and become truly undescended, annual follow-up examination until puberty is recommended.

Treatment: Orchidopexy

Why timing is everything

The treatment of cryptorchidism is surgical: orchidopexy mobilizes the testis and fixes it within the scrotum.

This recommendation is based on evidence that histological deterioration of the germinal epithelium accelerates beyond this age.

For the palpable inguinal testis, orchidopexy is a day-case procedure with very high success rates and rapid return to normal activity.

High intra-abdominal testes are managed laparoscopically, in staged fashion using the Fowler-Stephens technique when vessel length is insufficient. Hormonal therapy is not recommended by current guidelines to induce descent in unilateral cryptorchidism.

Postoperative Course and Long-Term Outlook

After orchidopexy, testicular position and growth are reviewed at scheduled follow-up visits.

In the long term, paternity rates among men treated in a timely fashion for unilateral cryptorchidism approach those of the general population, whereas fertility is more substantially affected in bilateral cases — a further argument for early intervention in this group.

From adolescence onward, boys with a history of cryptorchidism should be taught testicular self-examination, a simple habit that underpins the early detection of testicular cancer discussed in our related article on this site.

Frequently Asked Questions

This article is intended for general informational purposes only and does not constitute personal medical advice. Please consult a physician for diagnosis and treatment.

References

1. European Association of Urology (EAU). EAU Guidelines on Paediatric Urology. EAU Guidelines Office, 2025. uroweb.org/guidelines/paediatric-urology
2. Radmayr C, Dogan HS, Hoebeke P, et al. Management of undescended testes: European Association of Urology / European Society for Paediatric Urology Guidelines. J Pediatr Urol 2016;12(6):335-343.
3. Kolon TF, Herndon CDA, Baker LA, et al. Evaluation and Treatment of Cryptorchidism: AUA Guideline. J Urol 2014;192(2):337-345.
4. Pettersson A, Richiardi L, Nordenskjold A, Kaijser M, Akre O. Age at surgery for undescended testis and risk of testicular cancer. N Engl J Med 2007;356(18):1835-1841.