This is a very long post so sorry for boring you with my nerdy moment and feel free to skip to the last couple of paragraphs if you CBA to read the big explanation.
I absolutely HATE CB Digi. It's the conception indicator i hate most. I think it's just another expensive thing to stress pregnant women out.
I see so many women using these things to 'monitor' their hcg level to make sure they are still pregnant and it saddens me. These poor women are so stressed over it unnesecarily. And they shouldn't be if they knew how they work! (Feel free to skip this part if you aren't interested in HCG levels/pregnancy test lesson)
For those who aren't as nerdish as me, A non pregnant woman (And this is a very simplified as short as poss way of explaining all this!) can typically have a level of 1 - 5 ml/u of HCG in her system. This is the first big thing that can influence the results of any test and makes it absolutely impossible to know exactly how far gone you are just from HCG levels - Even with a quantative blood test which is the ONLY accurate way to monitor HCG levels, But because [as the following two scenarios show] there is such a massive margain between what are considered 'normal' levels for a pregnant woman even if they implant on the same day it's very difficult to tell how far they are even with a QBT!
So in scenario one, We have a woman who has 1ml/u of HCG in her system in a non - pregnant state. We shall say implantation is 8 days post ovulation. So, HCG typically doubles every 48 hours - So on 8dpo hcg is starting at 1ml/u
10dpo it doubles to 2ml/u
12 dpo - doubles again to 4mlu
14dpo - 8ml/u
16dpo - 16ml/u
18dpo - 32ml/u
20dpo - 62ml/u
22dpo - 124ml/u
So here you have a 5 weekish pregnant woman with 124ml/u of hcg in her system. A very sensitive pregnancy test could pick it up around 15 - 16dpo. CB digi would not detect it until 19/20dpo and would count it as low levels and probably say 1 - 2 weeks which is not right for her dates - Pregnant woman stresses, Takes more tests which cost a fortune!
In another scenario you have a woman who in her non pregnant state has 5ml/u of hcg in her system. She conceives and again implantation is on 8 days post ovulation. So starting with 5ml/u at 8dpo;
10dpo it doubles to 10ml/u
12 dpo - doubles again to 20mlu
14dpo - 40ml/u
16dpo - 80ml/u
18dpo - 160ml/u
20dpo - 320ml/u
22dpo - 640ml/u
So, Now we have two women, Both conceived and implanted on the same dpo but Woman number 1 wouldn't find out until 15/16dpo with a very senstive test, but woman number 2 would be able to find out at just 10dpo with a very sensitive test. CB digi for her would pick up higher levels of HCG and most likely tally with her dates as it would pick it up around 15dpo and probably say 1 - 2 or 2 - 3 which would be correct!
I have lost the will to live from explaining to people exactly why HCG levels cannot in any way be monitored accurately with urine tests - You can only tell from a quantative blood test exactly how much or if it's rising properly or not as so much influences a urine test - Even down to room temperature! Liquid intake, dye in the test[For none digi], reactants are all factors that influence results.
Big well done if you have got through my nerdy boring post!
