Serum progesterone is a test to measure the amount of progesterone in the blood. Progesterone is a hormone produced mainly in the ovaries.
Progesterone plays a key role in pregnancy. It helps make a woman's uterus ready for a fertilized egg to be implanted. It also prepares the uterus for pregnancy and the breasts for milk production.
Progesterone blood test (serum)
How the Test is Performed
A blood sample is needed. Most of the time blood is drawn from a vein located on the inside of the elbow or the back of the hand.
How to Prepare for the Test
Many medicines can interfere with blood test results.
Your health care provider will tell you if you need to stop taking any medicines before you have this test.
DO NOT stop or change your medicines without talking to your provider first.
How the Test will Feel
You may feel slight pain or a sting when the needle is inserted. You may also feel some throbbing at the site after the blood is drawn.
Why the Test is Performed
This test is done to:
Determine if a woman is ovulating
Evaluate a women with repeated miscarriages (other tests are used more commonly)
Determine the risk of miscarriage or ectopic pregnancy early in pregnancy
Progesterone levels vary depending on when the test is done. Blood progesterone levels start to rise midway through the menstrual cycle. It continues to rise for about 6 to 10 days, and then falls if the egg is not fertilized.
Levels continue to rise in early pregnancy.
The following are normal ranges based upon certain phases of the menstrual cycle and pregnancy:
Female (pre-ovulation): less than 1 ng/mL
Female (mid-cycle): 5 to 20 ng/mL
Male: less than 1 ng/mL
Postmenopausal: less than 1 ng/mL
Pregnancy 1st trimester: 11.2 to 90.0 ng/mL
Pregnancy 2nd trimester: 25.6 to 89.4 ng/mL
Pregnancy 3rd trimester: 48 to 150 to 300 or more ng/mL
Note: ng/mL = nanograms per milliliter
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.
Cynthia D. White, MD, Fellow American College of Obstetricians and Gynecologists, Group Health Cooperative, Bellevue, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.