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Avatar universal

Accurate or not?

Hello I had two ultrasounds  one at 7w0d exactly that had a range from 6w5d - 7w2d

I had my next ultrasound at a differ location at 8w0d exactly that had a range from 7w2d -8w4d.

I also had a 19w scan that was only off by one day from my two early scans

By having two ultrasounds at the earliest most accurate weeks, what are the chances that they both could be off by 5-6 days ??

Hope this makes sense!
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Avatar universal
Lol okay thanks so much !!
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
OK, I found it.  I didn't look back far enough.  This is what I said then, and still it looks right.  I don't think you have ANYTHING to worry about.  :)  Not even erroneous months in someone else's post.  lol

      Probable date of ovulation:  December 22
      Possible dates of conception:  December 18 to 26
      Due date:  September 14 (40 weeks)

Helpful - 0
Avatar universal
I had wrote on this website before but

Last period mid oct

Guy A- Nov 29 ( no protection but he did not finish inside me) I was on the pill however had missed about 2 or 3

Guy B- my boyfriend - Dec 16-jan 1
I had completely stopped taking birth control from dec on

Positive pregnancy test jan 11

Jan 13 ultrasound at the ER indicated I was about 5 weeks saw no baby just a sac

Feb 4 indicated I was 8 weeks 2 days I believe

Every other test added up to the same dates

Due date - Sept 14

From my information here it adds up to my boyfriend. But here and there I do worry and question it but it's a lot less now
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Well, if you are worried, write me your dates like this and we can go over them and see what they suggest.  

First day of last period (month, day)________
Sex with guy A (month, day)_______
Sex with guy B (month, day)_______
Ultrasound that said ____ of weeks (month, day)_________
Estimated due date based on ultrasound (month, day) _________

Other details (like, was protection used, when did you learn you were pregnant and was it by a home test or a blood test, etc.)
Helpful - 0
Avatar universal
Yeah i understand that confuses me since my mistake was Nov 29 so when I saw the dates it made me start thinking about my situation and if mayb it does tie down to the "mistake guy"
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Very good question.  It's worth noting that on this site a lot of times, the woman is texting fast and relying on memory for part of it, and that's usually where the error is.  

If the person has had an early ultrasound and was given an estimated due date from the ultrasound by the doctor, I don't usually go to the trouble to check that part of the story by hauling out a calendar and counting out the weeks to see if they also make sense to the story.  A due date given by the doctor from an ultrasound trumps everything, if the ultrasound was early in the pregnancy.  (Though, I will sometimes count out the weeks if nothing matches up in the story at all.)  Since AshBash's period start and estimated due date matched, and since I took it that the due date was given to her by her doctor, I didn't count out the weeks too.  But now that you have mentioned it, I have, and as you note, her ultrasounds should have been in January if they were 7th and 8th week ultrasounds and her due date was August 23.  It's actually pretty common in these posts for someone to write a wrong month; I'll pm her and see where the error lies, whether it is in the ultrasound dates, or whether it is in the due-date calculation.  It would certainly be important to her to know if she is actually due in July and not August!
Helpful - 0
Avatar universal
I was reading her dates and how she said she had a scan done feb 4 and was 7 weeks and 8weeks feb 11 but that's the same time I went (feb4) to get an ultrasound and was 8 weeks from her info she conceived end of nov and from mine I conceived end of dec but how could she be 7 weeks feb4 and me 8 weeks feb4 with two diff due dates
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Kasss99 -- When do you mean when you say "conception end of Dec"?  I get from December 22-24 for a due date of September 14 and being 8 weeks on February 4.
Helpful - 0
Avatar universal
It's weird that your were 7 weeks on feb 4th and is due Aug 23 because I am due sept 14 and was told I was 8 weeks on feb 4 leading to conception end of dec now I'm confused
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Hi, Jeree, I answered your other post.
Helpful - 0
Avatar universal
I had sex on the 20th of May with my boyfriend and then on the 26th of May I had sex with my ex... but the calendar on my phone is saying that I conceived on the 24th how is this possible please explain anyone
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
You're one of the lucky ones.  So many girls on here are trying to figure things out with only a 16th- or 18th-week ultrasound as a guide.
Helpful - 0
Avatar universal
Thanks I'll try not to stress about it all and be confident that it's the first guy ! I'm so happy I had two early ultrasounds
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Well, everything looks like Guy A, but it is about as close a thing as you would ever like to be.  You had sex with Guy A plenty of times around the time you would have ovulated according to both of your ultrasounds, and here is what the conception calculator I use says regarding the 8/23 due date:

     First day of last menstrual period:  November 16
     Probable date of ovulation:  November 30
     Possible dates of conception:  November 26 to December 4
     Due date:  August 23 (40 weeks)

Even with the wider margin it still suggests December 6 is too late.  

If the situation was instead that you had ovulated around the time you had sex with the second guy (Mr. December 6), you would have had both guy's sperm in your system, and the dates would not lead to a real conclusion.  But an egg (unlike sperm) only lasts 24-36 hours, so it means that if everything is really pointing to an ovulation at December 30, the egg would have had to be fertilized no later than December 31 or January 1.

This ties back to your question about the accuracy of ultrasounds -- in your seventh and eighth week, they might be off by a day either direction, but would not be off by several days.

That all said, I would do two things.  Go through your pregnancy with confidence that the baby is from Guy A.  And, get a DNA test when the baby comes.  It is too important to know, for the sake of both men, the baby, and you.  
Helpful - 0
Avatar universal
Lmp - November 16th
Guy a - November 26,28th, 30th and dec 1st
Guy b - dec 6th(early am)
Scan 1- feb 4th that was transvaginal measuring crl at 7w0d
Scan 2- feb 11th transvaginal crl measurement  at 8w0d
Both due datessc on the ausjsc 23rd
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
Well, I'm not so concerned about the accuracy of the scan as the accuracy of the analysis.  Could you write it out like this:

First day of last period (month, day)________
Sex with guy A (month)_______ 30 (if that was the actual day)
Sex with guy B (month)_______ 6
Ultrasound that said 6w5d to 7w2d (month, day)_________
Ultrasound that said 7w2d to 8w4d (month, day)_________
Estimated due date based on first ultrasound (month, day) _________
Estimated due date based on second ultrasound _____________

You can probably rely on the one that said you were either at the end of your sixth week or the beginning of the seventh week, but unfortunately if there were only 6 days between the guys, this makes things a bit more dicey.  List the dates as I've noted above, and we'll see if we can find any better news for you in them.
Helpful - 0
Avatar universal
I got my ultrasound  and the dr told me I was 7weeks exactly with that range I guess for the margin of error!
For example my ultrasound is saying I conceived on the last day of the month the 30th and I had sex with guy a days leading to the 30th and on the 30th and the day after. I had sex with guy b on the 6th of the following  month at  around 3am. My lmps are anywhere from 26-33 days , but both scans are matching as if I had a 29 day cycle.
How accurate can both of those scans be? What's your opinion
Helpful - 0
134578 tn?1693250592
COMMUNITY LEADER
How do you know that the ultrasound was at 7 weeks 0 days "exactly" when it said you were in a range from 6w5d to 7w2d?  Were you counting the "exactly" part from the first day of your last period?  If so, how regular are your cycles, 28 days on the dot?

If you are trying to split the difference between sex one day and sex 5 or 6 days later, you're kind of in a spot.  Despite the accuracy of early ultrasounds, sperm from guy 1 could still be in your system when you had sex with guy 2, if the time between them was that short.  Or are you allowing for that?  I guess the question is, when did you have sex with guy 1 and when with guy 2, and then when did you have your first ultrasound?
Helpful - 0
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