No clinically significant cross-reactivity has been demonstrated with follicle-stimulating hormone, human chorionic gonadotropin, free alpha subunit of pituitary glycoprotein hormones, or free beta subunit of luteinizing hormone. Cross-reactivity with thyroid-stimulating hormone (TSH) (<5%) might be observed at TSH concentrations of 500 mIU/L.
Some patients who have been exposed to animal antigens, either in the environment or as part of treatment or imaging procedures, may have circulating anti-animal antibodies present. These antibodies may interfere with the assay reagents to produce unreliable results.