title: Response to thyrotropin-releasing hormone stimulation tests in preterm infants with transient hypothyroxinemia of prematurity.
abstract: OBJECTIVE
  Whether hormone supplementation is necessary for infants with transient hypothyroxinemia of prematurity (THOP) remains controversial, and further analysis of the hypothalamus-pituitary-thyroid axis of infants with THOP is necessary.
  
  
  METHODS
  Thyrotropin-releasing hormone (TRH) stimulation tests were performed at 2 weeks of age in 50 infants with a gestational age of 30 weeks or less, and the data were analyzed retrospectively.
  
  
  RESULTS
  Subjects were divided into three groups; group A consisted of euthyroid infants, group B consisted of infants with THOP and group C consisted of hypothyroid infants. The basal and peak thyroid-stimulating hormone level of group C in response to TRH stimulation tests was significantly higher than the others, but no differences were observed between groups A and B.
  
  
  CONCLUSIONS
  The response of infants with THOP to the TRH stimulation test was not different from that of euthyroid infants, which suggested that their hypothalamic-pituitary-thyroid axis was appropriately regulated in infants with THOP.
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Iwanaga
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Matsukura
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Niwa
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Heike
mesh_terms: D005260:Female; D020249:Hormone Replacement Therapy / Q000379:methods*; D006728:Hormones / Q000008:administration & dosage / Q000378:metabolism; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000628:therapy; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007235:Infant, Premature, Diseases / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000628:therapy; D007564:Japan; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods; D012189:Retrospective Studies; D013268:Stimulation, Chemical; D013972:Thyrotropin / Q000032:analysis / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000008:administration & dosage / Q000378:metabolism; D013974:Thyroxine / Q000097:blood*
chemical_list: D006728:Hormones; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D013974:Thyroxine