Definition of Pregnanediol:

Pregnanediol is an inactive product that forms when the body breaks down the hormone progesterone. A test can be done to measure the amount of pregnanediol in urine. The urine test offers an indirect way to measure progesterone levels in the body.

How the test is performed:

A 24-hour urine sample is needed.

How to prepare for the test:

Your doctor may tell you to stop taking certain drugs that can affect the test. For example, ACTH may increase test measurements. Birth control pills or progesterone may decrease test measurements.

How the test will feel:

The test involves only normal urination, and there is no discomfort.

Why the test is performed:

Before progesterone blood tests were available, this test was used to monitor pregnancies and check for possible problems with the ovaries or adrenal cortex.

In women, progesterone is produced mainly following ovulation. During pregnancy, most progesterone is produced by the placenta. The main function of progesterone is to help the uterus prepared for possible implantation by a fertilized egg. After fertilization, progesterone is necessary for the development and maintenance of the placenta.

Some progesterone is also produced by the adrenal cortex. See: Adrenal glands

Currently there is little use for this test except in home ovulation predictor kits.