[1] However, polyorchidism can occur in conjunction with cryptorchidism, where the supernumerary testicle is undescended or found elsewhere in the body.

These cases are associated with a significant increase in the incidence of testicular cancer: 0.004% for the general population vs 5.7% for a supernumerary testicle not found in the scrotum.

[1] Polyorchidism can also occur in conjunction with infertility, inguinal hernia, testicular torsion, epididymitis, hydrocele testis and varicocele.

Prior to advances in ultrasound technology, it was common practice to remove the supernumerary testicle.

[3] Several cases have been described where routine follow-up examinations conducted over a period of years showed that the supernumerary testicle was stable.