Urinary Orotic Acid Levels in Normal Pregnancy and Pregnancy-Induced Hypertension

Abstract

Our objective was to study the urinary levels of orotic acid in normal pregnancy and in pregnancy-induced hypertension. Such levels were measured using high-performance liquid chromatography with column-switching. The levels of urinary orotic acid (μmol/g creatinine) in normal pregnancy (n = 14) were 6.9 ± 2.3 (first trimester), 10.1 ± 2.4 (20 weeks) and 12.0 ± 3.7 (30 weeks). In pregnancy-induced hypertension (n = 14), the corresponding levels were 6.5 ± 1.7, 7.8 ± 2.7 and 7.6 ± 2.3, respectively. Normal pregnant subjects individually showed a significant elevation at 20 and 30 weeks of gestation as compared with those in the first trimester (p < 0.01). A high consumption of arginine in nitric oxide production during normal pregnancy may cause a physiological elevation of urinary orotic acid. The absence of an elevation in pregnancy-induced hypertension may be associated with a decrease in nitric oxide production.