Table 3.
Estradiol immunoassay cross-reactivity
| Compound | Plasma/serum concentrations | Cross-reactivity in Roche assay | Likelihood of clinically significant cross-reactivity |
|---|---|---|---|
| Estradiol (endogenous compound) |
• 0.01 – 0.04 ng/mL (males) [37] |
100% |
High (assay target) |
| • 0.013 – 0.50 ng/mL (premenopausal females) [37] | |||
| • Up to 4.3 ng/mL (pregnancy) [37] | |||
| Estrone |
• Up to 0.06 ng/mL (males) [24] |
0.54% |
Low |
| • Up to 0.2 ng/mL (females) [24] | |||
| Ethinyl estradiol |
Up to 0.1 ng/mL while on medication [38-41] |
0.23% |
Low |
| Estriol |
• Up to 18 ng/mL in pregnancy [42] |
0.09% |
Possible contribution in pregnancy |
| • Up to 2.4 ng/mL in non-pregnant females [43] |