During clinical trials of Supprelin LA®, leuprolide stimulation tests were performed to determine adequacy of suppression. However, the use of this stimulation test to monitor suppression requires an expensive medication and collection of multiple blood samples. Alternative methods of monitoring pubertal suppression during gonadotropin releasing hormone receptor agonist (GnRHa) therapy have included both random and trough levels of Luteinizing Hormone (LH), estradiol or inhibin B. Recently, the free alpha subunit of pituitary glycoprotein (FASPG) has also been shown to be a potentially useful marker of hormonal suppression (Hirsch HJ, et al, JCEM 95:2841, 2010) as it undergoes a paradoxical rise following initiation of therapy, and reverts to baseline upon completion.