Increased 6-Hydroxycortisol Excretion in Pregnant Women: Implication of Drug-Metabolizing Enzyme Induction

Abstract

The effect of pregnancy on hepatic drug-metabolizing enzyme activity was investigated in nine healthy pregnant women using the ratio of 6-hydroxycortisol (6-OHF), to total 17-hydroxycorticosteroid (17-OHCS) in 24-hour urine as an index of the hepatic monooxygenase activity. The values of 6-OHF and the ratio (713 ± 250 μg/d and 0.323 ± 0.242; mean ± SD) before delivery were significantly higher than they were during early puerperium (395 ± 145 μg/d and 0.114 ± 0.055) and approximately three months after delivery (237 ± 67 μg/d and 0.066 ± 0.034). Although the values three months after delivery were comparable to those found in the nonpregnant group (n = 10; 228 ± 48 μg/d and 0.081 ± 0.031), 6-OHF values one week after delivery were significantly higher than those observed in the control group. These observations suggest that drug-metabolizing enzyme induction may occur during pregnancy.