ABSTRACT
BACKGROUND: Gonadotropin and steroid concentrations obtained in various laboratories cannot often be compared because of methodological differences. AIMS: to determine reference intervals for FSH, LH, T, E2, F and DHEA-S according to age and sex during the first year of life. METHODS: 1236 healthy infants (1-365 days of age) were recruited at Hospital de Niños in Córdoba, Argentina. Serum samples were analyzed using electrochemiluminescence, Cobas e601 analyzer. Reference Intervals and their confidence limits were estimated. RESULTS: Female FSH levels were higher than in males. LH and T levels were higher in males. E2 levels showed a difference between sexes after 60 days of age. F levels showed a wide variation, without differences between sexes. DHEA-S levels were higher at birth and decreased during the first year. CONCLUSION: These reference intervals may help to increase the diagnostic power for the assessment of endocrine disorders during the first year of life.
