Allopregnanolone, Urine Creatinine Ratio Unit Converter

Allopregnanolone is a neurosteroid produced naturally in the body from progesterone. It is one of the most potent enhancers of GABA-A receptor activity, the brain's main calming signaling system.

This test measures the amount of allopregnanolone in a urine sample, corrected for creatinine concentration to account for urine dilution. Creatinine correction allows a simple spot urine collection rather than a full 24-hour collection.

Allopregnanolone levels fluctuate with the menstrual cycle, rising significantly during the luteal phase and increasing up to tenfold during pregnancy. Levels drop sharply after delivery.

Allopregnanolone is synthesized from progesterone in a two-step process involving 5-alpha-reductase and 3-alpha-hydroxysteroid dehydrogenase. This conversion occurs in the brain (neurons and glial cells), adrenal cortex, ovaries, testes, and the placenta during pregnancy.