Inhibins and activins in human ovulation, conception and pregnancy

The activins and inhibins are glycoproteins that belong to thetransforming growth factor-ß superfamily, and, assuch, have diverse effects at many stages during growth anddevelopment. Originally identified by their effects on folliclestimulating hormone in males and females, the recent developmentof specific and sensitive assays for this group of polypeptideshas permitted the elucidation of their role in 'fine-tuning'the hypothalamic-pituitary-gonadal axis. This review articlefocuses on the roles of inhibin and activin in female reproductivephysiology with reference to possible future clinical applicationsin the investigation of infertility and abnormal pregnancy.