What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- The use of hormones, including those containing
estrogen or progesterone (such as birth control pills).
- The use of
medicines, such as ampicillin and clomiphene.
- The time of day when
you have the test. Progesterone levels normally fluctuate during the
- Having a test such as a thyroid scan or
bone scan that used a radioactive substance (tracer) within 1 week before the
- Where you are in your
What To Think About
- Levels of progesterone are higher during a
multiple pregnancy (such as twins or triplets) than during a single pregnancy
(only one fetus).
- Progesterone levels vary widely throughout the menstrual cycle.
So it is important for your doctor to know the first day of your last menstrual
Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
Chernecky CC, Berger BJ (2013). Laboratory Tests and Diagnostic Procedures, 6th ed. St. Louis: Saunders.
|Primary Medical Reviewer||Sarah Marshall, MD - Family Medicine|
|Specialist Medical Reviewer||Femi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology|
|Last Revised||February 22, 2013|
WebMD Medical Reference from Healthwise
February 22, 2013
This information is not intended to replace the advice of a doctor.
Healthwise disclaims any liability for the decisions you make based on this
© 1995-2014 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.