Please read ! Opks as pg tests !!
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| Thu, 08-28-2003 - 10:54pm |
I am a scientist and I thought I'd share what I know......
Chemically, LH and hCG are almost identical hormones. The difference is that hCG has an additional subunit called the beta chain. That's why you hear about quantitative hCG tests being called "betas"...because they are specifically testing for the beta subunit which is in hCG but not in LH. That's also why most pg tests will not turn + from LH. They react specifically to the beta subunit only. OPKs are a different matter. They are made to react to LH, which has the same chemical structure as hCG (the non-beta part). Therefore, if you are indeed pg you will get a +OPK. But it should be a true +OPK...like what you would see during your surge, not just 2 lines. If you are without a HPT but have some OPKs it will work if you are pg. I was afraid to take a HPT but I had a bunch of OPK s lying around so I tried one in the afternoon @ 12dpo. It was definitely + just like I had seen with my surge. I tested with a CBE and the line was faint but came up pretty quickly. I had a beta drawn the next morning and it came back at 93 (13 dpo).
If you get a TRUE +OPK in the 2ww, there are basically 3 possibilities:
1) you are pg and the OPK is detecting hCG.
2) you are not pg--somehow, you have misjudged your O time and what you are detecting is the LH surge just before O.
3) you are not pg--you have a disorder (i.e. PCOS) which causes fluctuating levels of LH throughout your cycle. In this case, again you are detecting a "surge" of LH.
I also wanted to add that while it is possible to get a +OPK in the 2ww and not be pg, I've never heard of someone actually being pg and NOT getting a +OPK (making the assumption that the test worked properly). Is there anyone out there who tested + with a HPT and not an OPK?
Personally, I find nothing wrong with using OPKs for HPT s as long as you understand why you could get a + and NOT be pg. The molecules are definitely closely related and there is overlap
| Thu, 08-28-2003 - 11:41pm |
| Fri, 08-29-2003 - 1:00am |
| Fri, 08-29-2003 - 6:56am |
