Time course of the serum gonadotropin surge, inhibins, and anti-Müllerian hormone

BERGADÁ, I; MILANI, C; BEDECARRÁS, P; ANDREONE, L; ROPELATO MG; GOTTLIEB, S; BERGADA, C; CAMPO,S; REY, RA

JOURNAL OF CLINICAL ENDOCRINOLOGY AND METABOLISM

Año: 2006 vol. 91 p. 4092 - 4098

0021-972X

CONTEXT: Newborns with ambiguous genitalia or males with nonpalpable gonadsusually require an early assessment of the presence and functional state oftesticular tissue. OBJECTIVE: Our objective was to characterize the preciseontogeny of the serum patterns of gonadotropins, testosterone, anti-Müllerianhormone (AMH), and inhibins in normal newborn boys. DESIGN: We conducted across-sectional and longitudinal study. SUBJECTS: Serum samples were obtained in 57 boys and 13 girls on d 2 of life. A second sample was obtained on d 7, 10, 15,20, and 30 (boys) and on d 30 (girls). MAIN OUTCOME MEASURES: Serum levels ofgonadotropins, testosterone, AMH, and inhibins were measured. RESULTS: In males, LH and FSH were undetectable or very low on d 2. By d 7, LH increased to 3.94 +/-3.19 IU/liter (mean +/- sd) and FSH to 2.04 +/- 1.67 IU/liter. LH/FSH ratios were0.40 +/- 0.11 (d 2) and 2.02 +/- 0.20 (d 30). AMH rose from 371 +/- 168pmol/liter (d 2) to 699 +/- 245 pmol/liter (d 30), and inhibin B rose from 214+/- 86 ng/liter (d 2) to 361 +/- 93 ng/liter (d 30). The inhibin alpha-subunitprecursor (pro-alphaC) remained stable during the first month of life.Testosterone levels were 66 +/- 42 ng/dl (d 2), 82 +/- 24 ng/dl (d 20), and 210+/- 130 ng/dl (d 30). A sexual dimorphism was observed in AMH and inhibin B(lower in girls on d 2 and 30), in LH/FSH ratio (lower in girls on d 30) and intestosterone (lower in girls on d 30). CONCLUSIONS: Sertoli cell markers AMH and inhibin B are the earliest useful markers indicating the existence of normaltesticular tissue.