title: Number of germ cells and somatic cells in human fetal testes during the first weeks after sex differentiation.
abstract: BACKGROUND
  This study presents the number of germ cells and somatic cells in human fetal testes during week 6 to week 9 post conception, i.e. the first weeks following sex differentiation of the testes.
  
  
  METHODS
  One testis with attached mesonephros from each of 10 individual legal abortions was used. After recovery of the fetus, the testes were immediately isolated, fixed and processed for histology. The optical fractionator technique, a stereological method, was utilized to estimate the total number of germ cells in ten testes and somatic cells in six of them.
  
  
  RESULTS
  The number of germ cells per testis increased from approximately 3000 in week 6 to approximately 30000 in week 9. The ratio of germ cells to Sertoli cells was approximately 1:11 and the ratio of germ cells to somatic cells was approximately 1:44 throughout this period.
  
  
  CONCLUSIONS
  For the first time, germ cell and somatic cell number have been determined during early human fetal testis development. Knowledge of the number of germ cells in this period may be very important, because several environmental pollutants are suspected to result in decreased semen quality in men born of mothers exposed to these pollutants during pregnancy.
authors.affiliation: Department of Obstetrics and Gynaecology, University Hospital of Odense, Sdr Boulevard 29, 5000 Odense C København Ø, Denmark. eske.bendsen@dadlnet.dk
authors.forename: Eske
authors.initials: E
authors.lastname: Bendsen
authors.forename: Anne Grete
authors.initials: AG
authors.lastname: Byskov
authors.forename: Steen B
authors.initials: SB
authors.lastname: Laursen
authors.forename: Hans-Peter E
authors.initials: HP
authors.lastname: Larsen
authors.forename: Claus Y
authors.initials: CY
authors.lastname: Andersen
authors.forename: Lars G
authors.initials: LG
authors.lastname: Westergaard
mesh_terms: D002452:Cell Count; D005333:Fetus / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology; D006801:Humans; D008297:Male; D012708:Sertoli Cells / Q000166:cytology*; D012733:Sex Differentiation; D013076:Sperm Count; D013094:Spermatozoa / Q000166:cytology*; D013234:Stem Cells / Q000166:cytology; D013737:Testis / Q000196:embryology*; D013997:Time Factors