The A1C ... How does it work?

I am awaiting the results of my A1C. I had the blood test less than 2 months after the last one. I’m wondering how the test measures the blood sugar. According to my pharmacist, it’s a three month reading so the higher sugars from the month before will be factored in???

The red cells normally live 120 days. During that time glucose molecules attach to hemoglobin & form glycated hemoglobin.
If your cells live longer or shorter than 120 days, it affects the A1c. See wikipedia\glycolysated hemoglobin for the types used in labs vs doctors’ offices.
It reflects the average glucose level of the cycle.
The main portion is the recent portion. Yes, earlier than 2 months is factored in but it won’t be much. It will show progress in reducing it.
Everything depends on how long your red cells live. Everyone has his own average life-of-the-cells.
By average I want to say also that your lows offset your highs.
Therefore, for an A1c you can believe or want to believe, you want to have the least lows possible.
In other words, keep the swings down over a 3 month period, and you’ll have a nicely reflective A1c.

Thanks so much for the detailed response Leo2. I think I understand how it works now.

Hi Leo2: My A1C for mid July read 8.2 which was what I expected based on your info.
It is down from the end of May when it was 10.1. I’m T2 on oral and I’ve never had a low so I believe this is fairly accurate. Thanks so much for helping me to understand the lab report.

Congratulations on the big improvement! Keep up the good work.