Serum FSH, LH, and testosterone concentrations in presumably fertile men: effect of age.

Abstract

Objective: Delineation of change in male hormone and gonadotropin levels from age 21 to 85.

Subjects: Healthy married volunteers with one or more children.

Methods: A 5-mL venous blood sample, serum separated within one hour; testosterone measured by direct RIA, FSH and LH by immunoradiometric assay and magnetic separation.

Results: FSH significantly higher from 6th decade, LH from 7th decade; testosterone lower from 6th decade.

Conclusions: Apparently, a rise in FSH and reduction in testosterone precede a rise in LH concentration.