Varying dose–response characteristics of different immunoassays and an in-vitro bioassay for FSH are responsible for changing ratios of biologically active to immunologically active FSH

Abstract

Serum FSH levels in fertile and infertile men were determined by applying the Sertoli cell in-vitro bioassay and six different immunoassays. Bioassay and immunoassay estimates were significantly correlated (r ranging from 0·78 to 0·86; PJournal of Endocrinology (1990) 127, 523–532