title: Hormonal changes in 3-month-old cryptorchid boys.
abstract: BACKGROUND
  Hormonal dysregulation has been suggested to be one of many etiological factors of cryptorchidism.
  
  
  OBJECTIVE
  The objective of this study was to assess the hypothalamic-pituitary-testicular axis in cryptorchid boys during the postnatal hormonal surge.
  
  
  METHODS
  This was a prospective, longitudinal, population-based study.
  
  
  METHODS
  The study was performed at two primary obstetric centers.
  
  
  METHODS
  Study participants included 388 Finnish and 433 Danish boys (88 and 34 with cryptorchidism, respectively).
  
  
  METHODS
  Clinical examinations were performed at 0 and 3 months. Blood samples were taken at 3 months.
  
  
  METHODS
  The main outcome measures were testis position and reproductive hormone levels.
  
  
  RESULTS
  Finnish cryptorchid boys had significantly higher FSH [1.59 (0.50-3.53) vs. 1.30 (0.49-2.92) IU/liter; P < 0.0001] and lower inhibin B [426 (254-770) vs. 459 (266-742) pg/ml; P < 0.015] levels than Finnish control boys [median (2.5th-97.5th percentiles)]. Danish cryptorchid boys had higher FSH levels than controls [1.47 (0.54-3.89) vs. 1.18 (0.41-3.04) IU/liter; P = 0.018]. Inhibin B levels in healthy Danish boys were lower than those in Finnish boys [380 (233-637) pg/ml; P < 0.0001] and were not reduced in Danish crypt-orchid boys [392 (236-672) pg/ml; P = 0.851]. Changes in hormone levels were strongest in boys with severe, persistent cryptorchidism, but were also detectable in mild and transient cryptorchidism. Effects on Leydig cell function were subtle, with an increase in LH in Finnish (but not Danish) cryptorchid boys vs. controls [1.97 (0.77-5.91) vs. 1.75 (0.58-4.04) IU/liter; P < 0.021], but testosterone levels remained within the normal range.
  
  
  CONCLUSIONS
  Our results support the hypothesis that cryptorchidism is associated with a primary testicular disorder, which could be a cause or a consequence of cryptorchidism. This malfunction is reflected by low inhibin B production in the Finnish cohort and high gonadotropin drive in both the Finnish and Danish cohorts.
authors.affiliation: Department of Physiology and Pediatrics, University of Turku, Kiinamyllynkatu 10, FIN-20520 Turku, Finland.
authors.forename: Anne-Maarit
authors.initials: AM
authors.lastname: Suomi
authors.forename: Katharina M
authors.initials: KM
authors.lastname: Main
authors.forename: Marko
authors.initials: M
authors.lastname: Kaleva
authors.forename: Ida Maria
authors.initials: IM
authors.lastname: Schmidt
authors.forename: Marla
authors.initials: M
authors.lastname: Chellakooty
authors.forename: Helena E
authors.initials: HE
authors.lastname: Virtanen
authors.forename: Kirsten A
authors.initials: KA
authors.lastname: Boisen
authors.forename: Ida N
authors.initials: IN
authors.lastname: Damgaard
authors.forename: Claudia Mau
authors.initials: CM
authors.lastname: Kai
authors.forename: Niels E
authors.initials: NE
authors.lastname: Skakkebaek
authors.forename: Jorma
authors.initials: J
authors.lastname: Toppari
mesh_terms: D002648:Child; D003456:Cryptorchidism / Q000097:blood*; D003718:Denmark; D005387:Finland; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D008137:Longitudinal Studies; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D012016:Reference Values; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013997:Time Factors
chemical_list: D012738:Sex Hormone-Binding Globulin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone