Epidemiology of UDT In Students of Tehran

  SUMMARY With the aim of surgical epidemiology nature of undescended testis, we examined 8034 school age boys in the city of Tehran. We invatted affected persons to Loghman-e-Hakim Medical Center for repeated examination and further diagnostic in­vestigations, results are: Among 8034 persons 82 had undescended testis, it means 1 .02 % , 56 % are in the right, and 33%  in the left, 11 % are bilateral. The most common site of testis in clinical study was canalicular testis which proved in surgery as well. For detecting the unpalpable testis, we requested inguinal & abdominal sonography. On the other hand, we studied etiologic factors of UDT in a case and case control. There were meaningful relation between use of drugs during pregnancy.