The fructosamine test is a blood test, like the A1c, except that it measures glycated protein in the blood instead of glycated hemoglobin. Sugar molecules that are present in your blood stick to proteins. These proteins circulate in your bloodstream for 14 to 21 days, so measuring them gives a picture of the amount of sugar in your blood for that time period.
When is the fructosamine test used?
Your doctor might order a fructosamine test if you've had a recent change in your medications or insulin, so he can monitor the effectiveness of the new treatments.
The test is also used in gestational diabetes because changes can happen very quickly during pregnancy. The shorter time span of the test allows the doctor to track blood glucose levels more closely.
Fructosamine - The Test. 24 Nov 2009. Lab Tests Online, Web. 28 Nov 2009. http://www.labtestsonline.org/understanding/analytes/fructosamine/test.html