Question 1

i had ultrasound on 01/20/14, with the baby measuring at 4.8 cm, is this accurate for a dating of 11weeks 4 days fetus?

Accepted Answer

Yes: Average length at this gestational age would be 4.1 to 5.4, so your baby definitely falls within that range.  Good luck!

Question 2

what is the error of margin for an ultrasound dating at 11 week 4 day, measuring the fetus crl at 4.8 cm?

Accepted Answer

Plus or minus, 5 day: The margin of error at that gestational age is typically + or minus 5 days.  That crl is definitely normal for that gestational age.

Question 3

is ultrasound dating the same accuracy for twins or multiples as
it is for a single fetus ?

Accepted Answer

Early sono: is very accurate at helping confirm the correct due  date, so should be good at discerning timing for delivery. Single or multifetal pregnancy, it works very well.

Question 4

is a dating ultrasound accurate showing 8 weeks if the fetus has iugr and woman has no known lmp? can the fetus actually be 20 weeks along and just look like 8 weeks due to iugr

Accepted Answer

Quite accurate dates: 20 weeks never looks like 8 weeks, just like a 20 year-old who was malnourished and neglected all his life will still not look anything like a normal 8 year-old boy. In a natural pregnancy, ultrasound dating that shows an 8 week fetus is an estimate that the pregnancy is 7-9 weeks. Avoid overthinking this, unless it is 100% impossible that there was a sperm meeting an egg 5-7 weeks ago.

Question 5

i had my 1st dating ultrasound on 5/23 dating me at 15 weeks 2 days edd 11/11! i didn't have unprotected sex until 2/26. could my ultrasound be wrong?

Accepted Answer

Ultrasound dating: That sounds about right. If you conceived on 2/26, you are about 15 weeks along.  First trimester ultrasound is accurate within 5-7 days.  2nd trimester ultrasound has accuracy of +/_ 2 weeks. 14 weeks is at the beginning of 2nd trimester.  Also, remember that a 15 week pregnancy is a 13 wk fetus.  The dates begin on the 1st day of your last period, not the date of conception.

Question 6

ok so i had my dating ultrasound. im a week ahead 8 weeks 2-3 days. they saying definitely over 8 weeks but i thought i was 7 weeks 4 days. we didn't even have to do transvaginal cause she said i'm definitely over 8 weeks. could they be wrong ?

Accepted Answer

Accuracy may vary: A careful transvaginal (not transabdominal)  pelvic sonogram (a "first trimester dating scan") performed by a certified sonographer using a well calibrated machine and proper scannig techniques is usually quite reliable and fairly accurate (plus or minus a few days) in dating your pregnancy. A follow up pregnancy sonogram in a few weeks should help answer your concerns and confirm your dates.

Question 7

lmp was 8/24/20, iui was 9/5/20. i had first ultrasound yesterday at what i thought would be 5w6d only saw gestational sac. is my dating wrong or should i be worried by us result? going back in 7-10 days for another us but cant  help worry?

Accepted Answer

Check with doctor: It sounds like you are seeing an infertility doctor. Consider scheduling a time to speak with them to go over your sonogram findings and determine if there is any cause for concern. The doctor treating you will have more information than we do. Generally,  a fetal pole is not seen on sonogram until week six.

Question 8

take ultrasound at 7weeks but doctor say there is no heartbeat is it too early are something is wrong with the fetus?

Accepted Answer

Need details: If you are truly 7 weeks then it should be easy to see the baby on sonogram. If there was no heartbeat then you need to get clarification from the doctor. If the gestational sac was small it may indicate the pregnancy is earlier than you think. If the sac measured 7 weeks then this may indicate a miscarriage. Contact the doctor ordering the sonogram for clarification

Question 9

are 11week ultrasounds accurate for dating? margin of error?

Accepted Answer

Varies: The range of error for an ultrasound at that point would likely be around +/- 8 days.

Question 10

how do you work out lmp from ultrasound dating scan?

Accepted Answer

Get a preg wheel: I give them to my OB pts if they want one, once u have a wheel it is easy.

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Doctor answers about:

How often are ultrasounds wrong in fetal dating

A member asked:

I had ultrasound on 01/20/14, with the baby measuring at 4.8 cm, is this accurate for a dating of 11weeks 4 days fetus?

A member asked:

What is the error of margin for an ultrasound dating at 11 week 4 day, measuring the fetus crl at 4.8 cm?

A member asked:

Is ultrasound dating the same accuracy for twins or multiples as it is for a single fetus ?

A member asked:

Is a dating ultrasound accurate showing 8 weeks if the fetus has iugr and woman has no known lmp? can the fetus actually be 20 weeks along and just look like 8 weeks due to iugr

A member asked:

I had my 1st dating ultrasound on 5/23 dating me at 15 weeks 2 days edd 11/11! i didn't have unprotected sex until 2/26. could my ultrasound be wrong?

A member asked:

Ok so i had my dating ultrasound. im a week ahead 8 weeks 2-3 days. they saying definitely over 8 weeks but i thought i was 7 weeks 4 days. we didn't even have to do transvaginal cause she said i'm definitely over 8 weeks. could they be wrong ?

A member asked:

Lmp was 8/24/20, iui was 9/5/20. i had first ultrasound yesterday at what i thought would be 5w6d only saw gestational sac. is my dating wrong or should i be worried by us result? going back in 7-10 days for another us but cant help worry?

A member asked:

Take ultrasound at 7weeks but doctor say there is no heartbeat is it too early are something is wrong with the fetus?

A member asked:

Are 11week ultrasounds accurate for dating? margin of error?

A member asked:

How do you work out lmp from ultrasound dating scan?

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