Trigger Testing - Ovulation Induction with Ovidrel

Waiting for Aunt Flo

Now is the dreaded wait.

According to much research and many studies, opinions, stories and first hand accounts, Ovulation should occur within 24-48hrs after the trigger shot, usually about 36hrs post injection.

However, my radiologist suspected that I was going to ovulate THAT DAY (the 1st of June) when she saw how big my follicle was, and my bloods supported that claim. She said I'd ovulate tomorrow at the latest.

So, I ovulated at the latest on the 2nd, shortly after taking my trigger. If I failed to ovulate, I definitely did by 8pm on the 3rd... It was confirmed that I ovulated with my progesterone levels and blood results later when I had a follow up blood test, so we know I ovulated, it's just the when that isn't certain.

I used to have a 12day luteal phase, but the last luteal phase was closer to 14days. So with all the pain and cramps I've had, I've been expecting my period to show all day today (14th of June, 2021). I wore white undies daring it to rear it's ugly head, but so far nothing.

At the VERY latest, my period is due by 8pm the 17th... so this is the scary wait. I should be getting positives if I'm pregnant... but I may also be getting positives if I test now due to the trigger injections I've given myself, which contain hCG (the pregnancy hormone that tests measure to determine whether you are pregnant or not). So the 18th will be a big determining day... I will not only have missed my period that should DEFINITELY have shown up by then, but I also have a blood test where I believe they will check my beta hCG levels and by then the results should be a TRUE positive if they are positive at all.

But I didn't know why the 18th was special. I tried researching and figuring stuff out, but everyone has different trigger dates based on their cycle, every reacts to the drugs differently, and not many people have Ovidrel to increase progesterone and test out how the trigger effects their hCG on pregnancy tests if they do.

Which I obviously have done, as you've read previously.

So, I went DETAILED. I researched THOROUGHLY. I found a lot of good studies, and a lot of bad ones too. And eventually I found enough information from enough fairly decent resources to do the working out and figure out WHY the 18th is the best time to test.

I looked at the amount of hCG present in Ovidrel 250ug injection (what I used as my 'trigger'), I considered how much of that hCG is actually absorbed by the body (bioavailable, which is just over 40%), and I looked at the amount of hCG when it maxes out in serum levels (blood levels) at 12-24 hours post injection (121 +/- 44 IU/L). I found the half life of the hCG in Ovidrel, which is 37.9hrs +/- 3.6hrs.

From all this, I could figure out an estimation of how much hCG is present in my body at any point after the injections. I erred on the side of safe, assuming I was on the far end of the spectrum that had a higher level of hCG absorbed from the Ovidrel injection, and also assumed that my Ovidrel had a longer half life (took longer to be excreted from my body).

The working is as follows (and if you can follow along, you're amazing, as this was literally some crazy working I did very late at night when I was procrastinating from study):

12-24hrs post injection – max hcg of 121 +/- 44

If max hcg reached at latest point possible:

165IU/L hCG 24 hrs post trigger (hrspt)

Half life of 38hrs +/- 3.6hrs

41hrs to be safe for half life:

165 – 24hrs (8pm 2/6)

82.5 – 65hrs (1pm 5/6)

TRIGGER @8pm 5/6 sooooo um....

If 7 hrs passes between 82.5IU at 1pm, and half life of 41 hrs...

If it drops 2.01IU per hour between 65 hrs and 106hrs, it would be at approx 14IU lower by 8pm.

68.5IU – 72hrs (8pm 5/6)

Um... that would still be lowering, but then the hcg from booster would increase it approx. 12-24 hours later? Sooooo, to be safe, assume it doesn't lower to make this easier lol, but then probably assume smaller amounts would be absorbed quicker so go for the 12 hour mark (lines up with tests I think, as these are serum levels and urine levels increase after serum levels, and with my pee tests they got strongest about 24hrs later). So...

68.5IU plus however much from the 60ug trigger at 8am 6/6).

Sooooo...

If 250ug is equivalent to 165IU/L then 60ug would probably equate to .. (165/250 = x/60, x = 165/250 x 60) ... 39.6IU.

So. At 8am 6/6 I'd have (probably less, but we are doing maxes to be safe so) 108.1IU

108.1IU – 84hrs (8am 6/6)

54.05IU – 125hrs (1am 8/6)

Next trigger was 8pm on 8/6 so 19hrs later... So. If it is to drop from 54.05 to 27.025 over the next 41hrs, that's 0.659IU per hour, so x19 = 12.5 drop. 54.05 – 12.5 = 41.55

41.55IU – 144hrs (8pm 8/6) TRIGGER + 39.6IU 12 hours later

81.15 – 156hrs (8am 8/6)

40.575 – 197hrs (1am 10/6)

20.2875 – 238hrs (6pm 11/6)

Trigger next at 8pm that day, so 2 hrs later, assuming that the next half life of 41hrs went approx./average of 0.2474IU per hour, so only 0.4948IU aka

19.7927 – 240hrs (8pm 11/6) TRIGGER

Note this should barely be visible by cheapies and still visible by FR, which was the case I think... didn't use FR around now, but seems to follow what my tests showed to some degree.

19.7927 + 39.6IU = 59.3927

59.3927IU – 252hrs (8am 12/6) Visible on cheapies, strong on FR.

29.69635IU – 293hrs (1am 14/6) Visible but lower on cheapies, strongish on FR.

14.848175IU – 334hrs (6pm 15/6)

7.4240875IU – 375hrs (11pm 16/6)

Now. What does this mean?

Basically, everything here follows along with my tests I have taken, which keeps me positive that I'm at least on the right kind of track.

If my fertility specialist assumed the same as me, that I am on the longer lasting hCG levels side of things, this means that by 8pm on the 17th, my levels should finally have dropped low enough that they would not be detectable on an at home pregnancy test (possibly, some studies have shown First Response to be as sensitive as 6IU and it takes a few hours for urine levels to reflect blood levels, so Urine Pee Sticks will be a little behind these numbers). By the morning of the 18th, a blood test would be definitively negative if I wasn't pregnant, the trigger would no longer be in my system enough to cause a false positive...

So if I'm pregnant on the 18th, then I'm pregnant. No trigger, nothing. That hCG would be due to a little baby implanted and causing my own body to produce the hormone, not any artificially injected stuff.

I love that I worked this out. It gave me reasons, it gave me certainty as to WHY I was waiting until the 18th, it made me understand everything they'd done and everything my body was achieving.

I also realise that when I get home tomorrow night (we are currently staying the night at my MILs so she can babysit my 2yo son whilst my partner and I leave for work super early before he wakes up tomorrow morning) I should be able to test and have some sort of possible answer.

My cheapie pregnancy tests should be negative (maybe a faint indent-like line if anything). My first response should definitely be fainter. This is all assuming I can manage to hold my pee for a few hours without drinking too much and diluting it, of course.

If my cheapie tests are still positive, and/or my First Response is the same or darker, then I will be incredibly amazingly absolutely hopeful that I am pregnant. And I will know for sure Friday afternoon around 3:30pm when the nurses ring me with my results.

I'm beyond excited.