Advanced search

When's the best time to get pregnant? Use our interactive ovulation calculator to work out when you're most fertile and most likely to conceive.

Quick question about blood tests (to check you're ovulating)

(10 Posts)
PeppermintPatty Tue 23-Jun-09 20:22:36

Just been to see GP.

She's referred me for a blood test for FSH/LH and progesterone.

She said to go for the test 7 days before my period is due to start. But on the blood form I've been given it says to go on day 21 of my cycle. Now I'm confused as day 21 of my cycle isn't 7 days before my period is due (as my cycles are longer than 28 days).
Which one is right?

Also does anyone know what these tests will show?

Thanks in advance

seanybosmummy Tue 23-Jun-09 20:31:12

Hi pp,for someone with a 28 day cycle it would be done on day 21 (7 days before next period), though for ppl who have a longer cycle than this you go 7 days before, so say for eg you have a 30 day cycle you therefore go on day 23 etc

I had this test done 2 weeks ago, but did not get conclusive results because my af has not showed up when i thought it would and therefore i had the test done too early, which meant my progesterone was not at avery high level which it would be after ovulation.

PeppermintPatty Tue 23-Jun-09 20:37:29

Thanks Seanybosmummy.

How annoying that your period didn't turn up on time after all that

Do you know what the tests show? I know progesterone shows that you've ovulated, but what does the LH and FSH show?

seanybosmummy Tue 23-Jun-09 20:56:13

Im not too sure why the lh and fsh test is done with the progesterone.

someone told me these are done on day 3 of your cycle and its only progesterone done on day 21. i think lh is the hormone that there is a surge in when you're about to ovulate, and fsh is follicle stimulating hormone which is something to do with the follicles the eggs burst out of at ov, but im not 100% sure tbh. I have no idea what the levels should be.

my progesterone was 2 and when i googled it there was conflicting opinions of what level indicated ov. one site said 8, one said 10 and another said 20!! How we are meant to understand it all is beyond me!! grin

It is very annoying that af didnt turn up but i am not losing hope just yet cause my gp said i could have ov later this month and therefore wont get a bfp just yet even tho my af is 3 days late.
so ive to go for a blood test on thur to check if im pg (fingers crossed).im sick of all this ttc malarky,its so frustrating and confusing.

good luck with your results smile

AttilaTheMeerkat Tue 23-Jun-09 21:18:00


LH and FSH are two very important hormones because they kickstart the ovulation process. Ideally when tested they should be the same but if there is an imbalance between the two this can be indicative of hormonal problems.

Irregular periods are often caused by a condition called polycystic ovaries. With PCO there is an imbalance between LH and FSH, in PCO the LH level is often raised compared to FSH.

LH and FSH are tested around day 3. Progesterone is tested much later; a day 21 test is standard in that regard and a level of 30 or over would indicate ovulation. LH and FSH are not tested at that time.

If periods are irregular anyway the blood tests can be done according to calendar days so this would be the 3rd and 21st of the month.

PeppermintPatty Tue 23-Jun-09 21:40:07

Thanks again.

Attila - why is my LH and FSH being tested at day 21 then? Do you think my GP has got it wrong?

She definitely didn't mention going for a test on day 3 just day 21, and it defo says LH, FSH and progesterone on my blood form


PeppermintPatty Tue 23-Jun-09 21:47:51

PS. also not sure if I need LH and FSH testing as I don't have any symptoms of PCOS and my periods are v regular. Are these just standard tests?

I'm confused and my GP didn't explain it all to me very well. I don't think she knew much about it anyway as she was looking things up in a book.

I just don't want to have to go back for repeat tests cos they were taken on the wrong day

poppy34 Tue 23-Jun-09 21:49:53

Waste of time IMHO- got tested 3 times and negative all times yet still got pregnant. Fell down with me as have irregular cycle

AttilaTheMeerkat Wed 24-Jun-09 06:53:45


How long are your cycles?.

No point at all in having LH and FSH tested on day 21; the standard test for those two levels is on day 3 as these kickstart the ovulation process. The day 21 test is primarily for progesterone only and this is a standard test as well.

Think your GP is indeed not well read on the subject.

PeppermintPatty Wed 24-Jun-09 10:33:07

My cycles are usually 30 or 31 days long, and VERY regular.

I'm going to ring the GP and query the tests as I think she hasn't realised that the tests need to be done on 2 different days.

Thanks for your help

Join the discussion

Registering is free, easy, and means you can join in the discussion, watch threads, get discounts, win prizes and lots more.

Register now »

Already registered? Log in with: