21 day blood test on day 23?

[Shoegal30]

Hi ladies, I could so with some advice please.

It's our 12 month of ttc #1 so I saw the doc yesterday and she wasn't massively helpful.

Anyway she is putting me forward for a 21 day blood test but as this lands on a Saturday, she has suggested I go for day the Monday which is day 23. Is there any issue in doing this? I have a 27 day cycle. Should I go for the Friday on day 20 instead?

With a short cycle, I would go for Day 20 personally - 21 is for 28-day cycle people, so day 20 should be perfect for a 27-day cycle . Mind, I should think your progesterone levels will still be high (or as high as they're going to get) on day 23... Do you know when you ovulate? It should be 7 days after ovulation, so the 'day 21' thing only works if you have a perfect 28-day cycle and ovulate on day 14. If you ovulate late and have a short luteal phase, day 20 could still be too early for you...

Thanks RaRaZ, I have a 27 day cycle and am not sure exactly when I ovulate but I normally get my 'peak' on the cbfm around day 12 so would that mean I ovulate around day 13/14?
So should I stick to day 23 then?

You know what I'd do? Have tests on both days, that way you'll definitely get your answer. They should be ok with that - I had three 'Day 21' tests last month lol.

My cycles are about 28 days and I went on day 23 for the same reason. I think inoculate late though so made sense to go later.

inoculate late?

Well that's a new one! Haha. Was meant to be I think I ovulate late!

I prefer the original lol, made me laugh

I have 27 day cycles too so I had a Day 20 test, which fell on a Sat. Our local walk-in centre did a blood test drop-in on a Sat morning so I went there. My GP's receptionist advised me of this.

The "day 21" test is just supposed to be mid-luteal phase (ie the middle somewhere between ovulation and your next AF). It does not need to be accurately on day 21; if you have ovulated then your progesterone level should be maintained at a high level between ov and AF (give or take a day either way) so anywhere between day 15 and 25 of a 28 day cycle would be reasonable. If it is low you can always repeat it a week later (if AF has not started) or the next month. They would normally repeat it at weekly intervals if you have long and/or irregular cycles as you don't know when your mid-luteal phase is. But I certainly wouldn't get it done on days 20 AND 23 as it will be a waste of time.
Good luck with it.

Jennifer: I disagree. I had three done, each two days apart last time and that was certainly not a waste of time: the first one showed no ovulation, the second suggested ovulation had occurred, but my progesterone wasn't particularly high, and the third confirmed ovulation with a nice high progesterone level. If I had waited a week, my levels would have dropped for my period and proved nothing.

I would agree that, if choosing one day, Day 23 is probably better...but if the OP has a short LP, her progesterone levels could have started to drop even by then. If unsure about the exact date of ovulation/exact length of LP, I'd go for two to make sure you catch it and don't have to wait for the next month.

If you get your peak on day 12 then you probably ovulate the following day. I think they do '21 day" tests because it assumes ovulation around day 14, so the test is ideally taken 7 days after you ovulate.
When I spoke to my GP about it, she didn't think a couple of days made any difference.
Having said that, if you have a short cycle, maybe you would be better going for the Friday rather than waiting until the Monday.(after all, Friday is closer to Saturday than Monday is!!) That's what I would do.
Good luck x