Progesterone test confusion? Which day to test

[SummerChild022]

Hi all, I’m very new to this. My doctor wants me to get a 21 day progesterone check. My last period began on October 3rd and I have a 25 day cycle. She told me to get my blood drawn on Friday the 18th October.

this doesn’t seem correct as it wouldn’t have been 21 days? My estimated ovulation day was the 14/15th October.

I’m also waiting to hear if I am still immune to chickenpox / rubella. The wait is torture, my partner and I want to start already, due to our age!

Thanks,

I’ve also read that instead it should be 7 days after your expected ovulation date? Not sure which to base it on / calculate?

Day 21 testing is a bit of a misnomer - it works if you have a textbook 28 day cycle with ovulation on CD14, but lots of people don't. You're correct that you should be aiming to test at 7 days past ovulation, which based on your dates would suggest that Monday 21st is probably the best day to test.

If you test on 18th you'll only be 3/4DPO and so your progesterone will inevitably be lower than it 'should' be - weird that she's suggested it so early, particularly as you ovulated pretty early in your cycle so using the standard ovulation on Day 14 calculation you'd only be 2DPO!

Thank you so much for explaining that! I will go on Monday.