Rookie mistake

I made a rookie mistake this week. Since I was feeling so optimistic about this cycle, I decided to test early – at 8 dpo (that’s 8 days past ovulation, for the non IFers). I saw the faintest second line, and woke C. to tell him that we were pregnant. I tried not to get TOO excited (after all, C. and I know all too well that a BFP is a far cry from a live baby…), but in my head, I had calculated the due date, lamented the end of my blog (okay, not much of a lament, but I thought about it nonetheless), and imagined how quickly all this ‘infertility stuff’ would be a distant memory. Not wanting to burst my bubble, C. gently asked “What’s the chance that it could still be due to the trigger shot?” to which I replied, “It’s been 10 days. There is no way that protein could still be detectable in my pee after 10 days!!!) I fantasized about our rainbow baby all the way to work, and then decided to Google it. And guess what?

hCG can totally remain at detectable levels…for up to 14 days following a trigger shot!

Ugh. I’m sure all the seasoned IFers out there are like “Duh!”

So what did I do? I tested again at 9dpo, 10dpo, and 11dpo. And the second line was like faint, fainter, gone. 😦

So today C. and I went to meet with Dr. Y. to plan our our next step. (One ‘perk’ from the accident: C. is available to go with me to all my appointments!) I found this meeting super depressing, which is to say, it was exactly like every other meeting at that office… “Yadda yadda yadda, diminished ovarian reserve, yadda yadda, born with all the eggs you’ll ever have, yadda, let’s do another day 3 blood test and antral follicle count, yadda yadda, we can try IVF but you’ll be lucky to get 5 eggs out, yadda yadda yadda…” You get the idea.

Rather than rehash the rest of the conversation, or the tear-filled ride home, I’d prefer to learn and then write about the biochemistry behind how home pregnancy tests work.

Here’s a nifty image I found online. I’ll attempt to caption it in my own words.


(A) So the purple blobs are hCG, which is present in the urine of pregnant women (and of wannabe pregnant women who had a trigger shot 10 days ago…)

Capillary action carries hCG along the stick (or down in this particular figure; nevermind that HPT instructions definitely do not say to hold the test with pee end up like that…) Anyway, capillary action carries hCG toward where the action is.

(B) The reddish things that look kind of like lobsters holding a blue balloon are the anti-α-hCG antibodies which were pre-deposited on the stick (between the pee end and the viewing end). The antibodies have a pigment attached (in the case of the test I used – FRER – the pigment is pink, not blue). They will grab the hCG (specifically the alpha subunit of hCG – for more about the structure of hCG, see this post) and hold on tight…and be pink.

Now, capillary action will carry the bound-to-hCG anti-α-hCG antibodies, and the free anti-α-hCG antibodies (there are extras that don’t get any hCG) along the stick.

(C) At the ‘test line’, there is a line of anti-β-hCG antibodies (blue lobsters in the figure, although they are actually colorless) that are fixed to the stick. These antibodies also grab onto hCG (specifically, the beta-subunit) and hold tight…and don’t go anywhere. Everybody holds on tight, and the resulting group of anti-β-hCG—hCG—anti-α-hCG sandwiches appear as a pink line on the stick.

Meanwhile, the free anti-α-hCG antibodies (that is, the ones that didn’t get any hCG) continue to be carried by capillary action along the stick.

(D) Finally, the free anti-α-hCG antibodies reach the ‘control’ line, where there is a line of antibodies that specifically bind to the anti-α-hCG antibodies (no hCG needed). These antibodies are the green turtle-heads in the figure, and are themselves fixed to the stick. The resulting antibody—anti-α-hCG complex appears as the pink control line.

I go in for a blood pregnancy test (which works a bit differently; but I’m too lazy to figure out how right now…) on Saturday, but with a negative HPT at 11dpo, I’m decidedly not optimistic about it. I’m also not optimistic about moving forward with IVF, but I’m sure that will pass. In the mean time, I think I’ll console myself with a glass of wine tonight.

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  1. Cool lesion! I triggered on Tuesday and POAS yesterday just for fun, my blue line was really faint …

  2. Interesting lesson! I always think about things like this while I’m taking the tests, actually. I think that’s because I am trying to think about anything besides the fact that it is going to be negative again. And I always wait and watch to see if that test line is going to catch whatever little hCG bits are supposed to be caught by it. I’m sorry that you got yourself all hyped up about the trigger tease. It’s cruel, isn’t it?

    • Thanks for visiting!
      Yes, it is cruel. Almost as cruel as the pregnancy-mimicking progesterone symptoms (vivid dreams, waking up 10 times per night to pee, sore boobs, swollen boobs, and backne…all when I’m not remotely pregnant). Infertility is a real bastard!

  3. AAR

     /  May 4, 2013

    sorry, knalani!! have a good cry, enjoy a 2nd glass of wine, and hang in there. we’re rooting for you!! 🙂 (BIG HUG!)

  4. So sorry to hear this! Give yourself some time before you think about the next steps, you may feel much differently about IVF after a little while xx

  5. Oh no!!!!!!! I am so sorry about the hCG confusion. If I wasn’t obsessed with Googling every little thing I’m doing, I wouldn’t have known about the hCG staying in your system that long. No one at my RE’s office ever told me– I had to ask the nurse. It’s probably something they should warn people about. Good luck on planning your next steps. Don’t give up! And enjoy your wine 🙂

  6. Hi! I have diminished ovarian reserve as well. I just had a fresh IVF cycle, but I had all of the viable embryos frozen after pre-implantation genetic testing. I also had one round of IUI with femara in the past. Like you, I tested at day 8. I had NEVER seen a positive test until that moment. I remember thinking, “so these things really do work.” I, unfortunately, knew it was the trigger, and of course two days later, I got the negative that used to always greets me. So believe me, I know your pain. *sigh* However, I have to declare that I will NEVER see the negative mark again. It’s not an option.

    • Thanks! My protocol also involves freezing any embryos we get for a full cycle before transfer. Here’s hoping it works for both of us!

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