How accurate are CB digis?

[Sausagesaurus]

Hi ladies,

I am new on the pregnancy board but was on the conception board for a short time.

I got a BFP with a CB digi last Tuesday that said I was 1-2 weeks. However, the NHS website said my dates suggest I am 4 weeks (that was on Friday) and I saw the midwife today who said that I was nearly 5 weeks.

Would you be more inclined to go with the midwife/NHS than the CB digi?

Thanks

Nhs and midwife will count from first day of last period.
Cbdigi counts from conception.
There's normally about 2 weeks discrepancy.

Congrats!

Hi, congratulations and welcome :)

The tests are all saying the same thing, they just record it differently. You're 2 weeks since conception but 4/5 weeks since last period (llp) depending on your cycle length.

Thank you for the replies and congratualtions it still hasn't really sunk in!

That makes sense. As the booking appointment and scans (I assume) will be based on the date of my last period, I think I will go with that, makes it less confusing for me!

Thanks ladies

Yes, clear blue digital gives time from conception. So if you are 1-2 on the test, you are 3-4 in real life, and so on. So getting 1-2 weeks on Tuesday and being 4 weeks on Friday are, weirdly, the same thing!

Also bear in mind that a week is a short time. So you could have been 4+3 on Friday (which the MW just expressed as '4 weeks'), you'd now be 4+6 (aka 'nearly 5 weeks'), etc.

hi there
congrats sausage - I got my bfp too and it too hasn't sunk in :)

I am also confused about the digi test

mine came up with pregnant 3+ but that doesn't correspond to my dates at all as my LMP was on 29 October - am now panicking that something is wrong as the pregnant 3+ would suggest I am 5 weeks but I am only 4 weeks and 4 weeks and 5 days - is this correct or is my befuddled pg state getting even more confused ?? Also does that mean my hcg levels are too high which surely doesn't sound good :( oh dear panic :(

any clarification on this would be gratefully received

jolly - What is the problem with that? 29th October makes you nearly 5 weeks. So you would say 3+ weeks on a CB digi. Believe me, it's not so accurate it can detect to the day and give a different result at 4+5. There's a reason that the brackets are 1-2, 2-3 and 3+.

Also, even if you did have high HCG, it could just mean you ovulated a day or two earlier than you thought. Or it could be twins!

All the instructions in the digis explain that you need to add on 2 weeks to get the result

thanks penguins - wow twins - now that would be something!!

Am fine with it all as long as everything is healthy and normal - have just been scaring myself senseless with all the google searching about high hcg numbers
am feeling a bit more relieved with that now you have clarified it
so that would make me nearly 5 weeks?

how did you get an appoinment with the midwife sausage? I am struggling to get an appmt with my gp let alone a midwife!

In the nicest possible way, neither the GP nor the midwife particularly need to see you now unless for some reason you need early pregnancy support. In my area MW's won't see you until at least 8 weeks.

Thank you everyone for the responses I really appreciate the clarification

jolly congratulations to you too! it's so exciting!

In regards to my appointment, I just called my GP who gave me the direct number for the community midwife. It was only a walk in appointment and a tick box exercise, was over in about 15 minutes but they are arranging my booking appointment.

penguin is right though, I think it all depends on the area. You could always just try calling the community midwife directly? Maybe try googling the number? For what it's worth, my appointment was in a local sure start centre, the details were also listed on their website, maybe you could look at the local children's centres in your area to see if they have a similar walk in antenatal service if you want to see a midwife.

I hope you have a happy pregnancy

CBDs can apparently be out +/- 10 days either way. Having hung out on the conception board, they just seem to be a massive pain in the arse!

CBD have quite wide thresholds, and it completely depends on your natural HCG levels. 1-2 weeks is 50-200miu, 2-3 weeks is 200-2000miu and 3+ is over 2000miu. They drove me nuts when I got my bfp, and made me worry I was going to miscarry because my HCG didn't double every 2 days. I got 1-2 weeks at 12DPO, then 2-3 weeks at 18DPO, 2-3 weeks AGAIN at 27DPO and only got 3+ at 28DPO (or exactly 6 weeks pregnant).

Try not to worry too much about it - the weeks are based on averages and some people will see levels rise slower than others, but it doesn't necessarily mean anything.