First pregnancy - working out dates…

[ecossegirl91]

I have my first scan on 20/04 (eeek!) and I guess I’m just a little bit nervous about my dates…
My LMP was 19/01 however this was after finishing my pill pack on 14/01 therefore I don’t know my cycle length, when I ovulated etc so not a “true period”.

My LMP will put me at 13 weeks on the scan date and I got my bfp on 25/02 (attached pic, it’s quite a strong positive, taken with fmu!) however I randomly took a clear blue digi on 17/02 and it was negative (it was in the afternoon tho and not fmu) so could have been wrong as you would think based on my LMP it would be pos?

Anyway, this is what is making me think maybe I’m a week behind my LMP and on the scan date I’ll be 12ish weeks?
Sorry for rambling - what do you guys think? I don’t think I could be much less than that based on the bfp date? Like it would be unlikely they would tell me I’m only 9 or ten weeks? I don’t know why this is bothering me so much tbh! Guess I’m nervous I think I’m 12/13 and they say 9/10!

Thanks in advance for anyones thoughts!

I wouldn't worry to much-they'll give you an EDD based on your scan anyway

Yes don’t overthink. They will just base the due date off your scan.

I had a similar situation to this - I took a test and it was negative around when my period was due, 10 days later took another as period still hadn't arrived and it was positive.

At my dating scan, based on LMP I should have been 12+6, but was put back to 11+1 and had to go back for a second scan two weeks later as the baby was too small for the measurements. At the second scan I was dated 13 weeks exactly.

It could be that your first test didn't pick it up (those digital ones aren't as reliable as the red dye ones) or you could be similar to me and ovulated a bit later than you thought based on LMP!

Hello! I relate to this, I finished my pill at the beginning of January, last period was around 25th Jan, but then tested negative up until when I thought my period was due (23rd February), and tested positive on 27th February. I had an early scan due to a little scare which showed I was exactly a week behind what I would have been if my period had counted/my ovulation cycle was 28 days. I started counting from the measurement so now I’m 10 weeks tomorrow (but thought I would be 11 weeks based on my first calculation if that makes sense?). At least if you measure a little smaller than expected, you know the reason why and won’t have to be too concerned :) xx

Going by LMP from 19th January you would be 13 weeks on 20th April.

If you were 4 weeks pregnant on 25th February (the day of your positive test), you would be 11w5d on 20th April.

There isn't that much margin for error with your dates. 9 days in total.

That test line looks stronger than I would expect for 4 weeks, so given that you got a negative test on 18th February, I would guess that on 25th February you were probably about 4 and a half weeks pregnant.

If there's a significant difference between your LMP date and your scan measurements they will probably adjust your due date. But this is all very much within the margin of error.

A full term baby can be born any time between 37 and 42 weeks, if that helps put things into perspective for you.