CYP3A4 and preeclampsia: To evaluate CYP3A metabolism across a spectrum of pregnancy states in humans, plasma 4β-OH-CHO concentrations and the plasma 4β-OH-CHO to CHO ratio (endogenous biomarkers of CYP3A activity), were quantified in healthy nonpregnant volunteers, healthy pregnant volunteers, and pregnant patients diagnosed with preeclampsia (Table 2).