Estimating the testis volume during the fetal period using the stereological method

The purpose of the present study is to assess the development of seminifero us tubule volume, stromal volume and total testis volume in the human fetal testis during the fetal period using the stereological method. In this study, we examined 90 testes of 45 human fetuses with no congenital anomalies and pathologies. They were aged between 12 and 40 weeks and loca lized between the scrotum and the abdomen. Total testis volume, seminiferou s tubule volume, and stromal volume were estimated using Cavalier Principle s. The weight and density of the testes were calculated as well. During the fetal period, the testes were firstly found on the right in the 27th week and on the left in the 32nd week in the scrotum. Ar the end of th e third trimester and full term, the migration of the testes into scrotum w as completed (98%). When the second trimester, third trimester and full ter m fetuses were compared, the differences between testis volumes were signif icant (p<0.001). The density of the testes between the groups was not signi ficant (p>0.05). Testis parameters during the fetal period were not signifi cantly (p>0.05) different between the right and left testes localization. T he correlation between the fetal testis parameters was significant (p<0.001 ). Towards the end of the fetal period, the rate of seminiferous tubule volume to stromal volume changed in the favor of seminiferous tubule volume. It w as observed that interstitial tissue became more regular and had a good org anized structure with the progress of gestational age. In the third trimest er, the lumen in the seminiferous tubules became more regular and clear and the interstitial tissue had a clear appearance. <(c)> 2001 Elsevier Scienc e Ireland Ltd. All rights reserved.