Definition of Serum progesterone:

Serum progesterone is a test to measure the amount of progesterone in the blood. Progesterone is a hormone produced mainly in the ovaries.

In women, progesterone plays a vital role in pregnancy. After an egg is released by the ovaries (ovulation), progesterone helps make the uterus ready for implantation of a fertilized egg. It prepares the womb (uterus) for pregnancy and the breasts for milk production.

Men produce some amount of progesterone, but it probably has no normal function except to help produce other steroid hormones.

How the test is performed:

A blood sample is needed. For information on how this is done, see: Venipuncture.

How to prepare for the test:

Your health care provider may tell you to stop taking drugs that may affect the test. Drugs that can interfere with the test include progesterone and birth control pills.

How the test will feel:

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed:

This test is done to:

• Determine if a woman is ovulating
• Evaluate a women with repeated miscarriages, but other diagnostic tests and treatment are more commonly used for this purpose
• Determine the risk of miscarriage or ectopic pregnancy early in pregnancy