Day 21 serum progesterone test - Fertility Network UK

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Day 21 serum progesterone test

Emmyeve profile image
17 Replies

Hi guys, another quick question. I have to have certain tests done on certain days of cycle including serum progesterone test on day 21 on cycle. Of course my day 21 of this cycle falls on a Sunday. If I get it done on day 22 will it make a difference? I’m guessing if they’ve specifically said day 21 then it must be done on that day ☹️

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Emmyeve profile image
Emmyeve
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17 Replies
Cinderella5 profile image
Cinderella5

Check with your clinic but I would think a day out would be ok. I had my 21 test done on day 22 an it was ok but always best to check with your clinic as you dont want to waste a blood!xx

Emmyeve profile image
Emmyeve in reply to Cinderella5

Thank you. Do you know what that test is for exactly?

Cinderella5 profile image
Cinderella5 in reply to Emmyeve

Its usually to check that you have ovulated, this would show in progesterone levels.xx

Emmyeve profile image
Emmyeve in reply to Cinderella5

Thank you. If it’s to test that I’ve ovulated but my ovulation tests showed I was ovulating day 11/12 this cycle, do you think that will alter the day I should do that protesterone test? For example, if that test is to be done 7 days after ovulation and my ovulation tests gave indication that I was ovulating on day 12... then I should be doing the progesterone test on day 19 surely?

Cinderella5 profile image
Cinderella5 in reply to Emmyeve

Your clinic should guide you on this but as far as Im aware they're only looking for a rise over a certain level to show ovulation.xx

SBeanbag profile image
SBeanbag

How many days are your cycle? generally test 7 days prior to the end so - day 21 for a 28 day cycle

Emmyeve profile image
Emmyeve in reply to SBeanbag

Usually between 26 and 29

SBeanbag profile image
SBeanbag in reply to Emmyeve

I would go in the Monday then, but as cinderella5 says I would check with the clinic.

Emmyeve profile image
Emmyeve in reply to SBeanbag

Thank you. If it’s to test that I’ve ovulated but my ovulation tests showed I was ovulating day 11/12 this cycle, do you think that will alter the day I should do that protesterone test? For example, if that test is to be done 7 days after ovulation and my ovulation tests gave indication that I was ovulating on day 12... then I should be doing the progesterone test on day 19 surely?

in reply to Emmyeve

The progesterone spike comes a bit later than the LH surge that you get when you test for ovulation. That is why it is done a week before your period and not actually at the time of ovulation. X

SBeanbag profile image
SBeanbag in reply to

The progesterone surge is not just there for one day so should still be able to detect it a day or two later and Zoe is correct they are looking at different things - at the end of the day no one test is more important than any other and progesterone is part of the jigsaw - they will go on and do other tests to decide on the best advice and treatment for you x

Emmyeve profile image
Emmyeve in reply to SBeanbag

Thanks again. Really appreciate it

I couldn’t do a progesterone blood test due to work commitments on day 21 so I did it the day afterwards on day 22 it was fine. Let them know and I’m sure it won’t be an issue xoxo

Lynnr54 profile image
Lynnr54

I would just flag with them that your tests show you ovulated early this month. You say your cycles are between 26 and 29 days - do you have a fairly consistent luteal phase I.e. if you ovulate early does that correlate with a 26 day cycle? If so then I’d probably test on the Friday rather than the Monday but definitely worth checking with your clinic/GP.

I have quite long cycles and when I first had tests many moons ago I didn’t know then what I know now, so I went along for my test on day 21 even though I’d only ovulated on about day 18/19. Of course it showed up as an abnormal result. When I got to my clinic and they realised what had happened they retested me on a later day in my cycle and my results were still low but just about in the acceptable bracket so they weren’t worried about them.

Good luck with the tests - hope you get some answers from them.

Emmyeve profile image
Emmyeve in reply to Lynnr54

Thank you for your reply. I’ve always been 28 days like clock work but had excision surgery in December and since then they’re a little either side. But I’m pretty sure I ovulate around day 10-12. I was going to ask the GP if they’d be kind enough to test me both Friday and Monday which would cover both but I very much doubt they’d do that so I’ll probaby go for the Friday & I’ll make a note for the clinic that they’ve tested me on day 19 because I think I ovulated on day 12.

Lynnr54 profile image
Lynnr54 in reply to Emmyeve

Sounds sensible. Good luck!

LKT1 profile image
LKT1

Hi! I had this issue and it depends if your cycle is usually 28days. My day 21 ended up being a Saturday and I didn’t have the test until the Monday...on receptionist recommendation...however they didn’t take into account my cycle is only 25days long. This meant my levels of P were showing incorrectly for that time of the cycle. Dr even said I don’t ovulate even though I regularly took ovulation tests which said I did.

I saw a different Dr who said the test was a waste of time as it should have been done on around day 18 as my cycle is shorter. Got the results back as normal after that one! So basically if you have a normal cycle then I hope one day out will not make too much difference. I would ask your GP but they may suggest; If you have a shorter cycle deduct the difference from 28 days and go then. If you have a longer cycle add the difference and go after. Alternatively wait until next cycle if that falls on a weekday. Hope this makes sense. X

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