Pregnanediol-3-glucuronide (PdG)

Pregnanediol-3-glucuronide (PdG) is the primary urinary metabolite of progesterone, produced in the liver through the conjugation of pregnanediol with glucuronic acid by UDP-glucuronosyltransferase enzymes [1, 4]. It serves as a critical non-invasive biomarker in reproductive medicine, where its levels in urine are used to confirm ovulation and assess the functional status of the corpus luteum during the luteal phase of the menstrual cycle [1, 6]. While PdG itself is not a therapeutic target for pharmacological intervention, its measurement is essential for diagnosing luteal phase deficiency, monitoring early pregnancy, and managing infertility [4, 7]. Elevated levels typically indicate successful ovulation or pregnancy, whereas low levels may be associated with anovulation or an increased risk of miscarriage [1, 8]. As an inactive excretory product, it reflects systemic progesterone production rather than acting as a site for drug binding or action [1, 5].

Other names

5beta-Pregnane-3alpha,20alpha-diol 3-glucuronidePregnanediol glucuronideP3G5β-Pregnane-3α,20α-diol 3α-glucuronidePregnanediol-3alpha-glucuronide

Pregnanediol-3-glucuronide is a metabolic byproduct and does not possess a mechanism of action as a therapeutic target; it is used exclusively as a biomarker for endogenous progesterone levels.