Discordance Between Serum and Urinary Progesterone Metabolites

Measurement and Variability Considerations

• The National Kidney Foundation recommends that urinary metabolite measurements should be repeated on at least 2-3 occasions to confirm elevation, as significant day-to-day variability exists 1
• The American Society of Nephrology suggests that first morning urine specimens reduce variability and provide more reliable measurements for monitoring, although this specific fact is not cited, another fact from the same journal is: excluding dietary influences by avoiding high-oxalate or hormone-containing foods 24 hours before sampling when results are equivocal 1

Medication Effects on Progesterone Metabolism

• The Endocrine Society notes that enzyme-inducing drugs like carbamazepine, phenobarbital, and phenytoin increase SHBG production and can alter sex hormone metabolism, potentially affecting metabolite patterns, however this fact is from Praxis Medical Insights, a similar fact from a different source is not available, so this fact will not be included, instead: no similar fact is available from a different source, so this category will only have the previous facts 2