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Doctor insights on: What Is More Accurate Lmp Or Measurements

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How accurate are the baby ultrasound measurements? is it possible to give or take two weeks ?

How accurate are the baby ultrasound measurements? is it possible to give or take two weeks ?

It depends: In 1st trimester the measurements are very reliable. At the anatomy screen/survey (usually 18 - 22 weeks) the dating can be off by a couple of weeks. Standard measurements include two head measurements (the most accurate) and measurements of the abdomen circumference and the femur (thigh bone). Dating in the 3rd trimester becomes less accurate. ...Read more

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Confused on due date. Late in pregnancy which is more accurate, ultrasound or fundal height?

Confused on due date. Late in pregnancy which is more accurate, ultrasound or fundal height?

Earlier info: Your due date shouldn't change in late pregnancy. It is established by info about your last period and earlier ultrasound. ...Read more

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Can you tell me how precise is a transvaginal untrasound at determining conception and due date?

Can you tell me how precise is a transvaginal untrasound at determining conception and due date?

Pretty good: The dating is accurate to about a week as long as the sonographer can see the baby early on. The due date though is really variable. ...Read more

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Is a gestational age reading accurate on a 10 week ultrasound? And what exactly are they measuring?

Is a gestational age reading accurate on a 10 week ultrasound? And what exactly are they measuring?

Accurate: A first trimester ultrasound is highly accurate. They are measuring what is called a crown (top of the head) rump (bottom of the bum) length. The length is compared to average size embryos to come up with a gestational age. ...Read more

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Why are ultraound edd more accurate than your LMP edd?

Why are ultraound edd more accurate than your LMP edd?

Not always true : Early in fetal life all babies grow at the same rate. The longer into the pregnancy the more each baby grows slightly differently. Therefore, early in pregnnacy we can measure the size of a baby and very accurately predict the due date. Later on though, the sonographic measurements less accurately predict the due date. ...Read more

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If LMP and 12 week ultrasound correlate, would the u/s be considered more accurate since the LMP is known? Or is there still 1 week margin of error?

If LMP and 12 week ultrasound correlate, would the u/s be considered more accurate since the LMP is known? Or is there still 1 week margin of error?

LMP for dating : If in the first trimester, we go with the lmp unless the sono is over a week off. I we give the ultrasound date, but say "consistent with dates" the and still use the lmp date. ...Read more

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Which gestational age is more accurate, LMP based or ultrasound one? By LMP i am 27weeks and 4 days.ultrasound says 28 weeks

Which gestational age is more accurate, LMP based or ultrasound one? By LMP i am 27weeks and 4 days.ultrasound says 28 weeks

Gestational age: Your LMP is usually more accurate than ultrasound especially at 27+ weeks. Ultrasound is more accurate in the first trimester and gets less accurate the further along you get in the pregnancy. ...Read more

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Which is more accurate at detecting the baby's due date? The five or eight week ultrasound?

Which is more accurate at detecting the baby's due date? The five or eight week ultrasound?

Ultrasound dating: First trimester ultrasound is accurate within 5-7 days. 2nd trimester ultrasound has accuracy of +/_ 2 weeks. Lmp dating also assumes a 28 day cycle. There is no test that can date conception more accurately than a 1 week window. Due date is based on lmp unless us off by more than 1 week 1st trimester or 2 weeks in 2nd. ...Read more

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How accurate is an ultrasound due date estimate?

How accurate is an ultrasound due date estimate?

Best on earlier u/s: Ultrasounds use composite data obtained during the exam to determine an EDD (estimated date of delivery). This date will also have a +/- number of days giving an accuracy range. First trimester ultrasounds are accurate to within about a week, second trimesters estimates are accurate within about 2 weeks, and third trimester scans about 3 weeks. ...Read more

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Is conception more accurate based off LMP or 9 week ultrasound?

Is conception more accurate based off LMP or 9 week ultrasound?

Both is best: The most accurate dating is where the 1st trimester ultrasound is within a week of the lmp dating; that confirms the lmp dating. If the 9 week ultrasound gives dates greater than 1 week from what's predicted by the lmp then the lmp is not accurate and the ultrasound dating should be used. ...Read more

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Which test is more accurate in measuring proximal abdominal aorta size in men: ultrasound or mri/mra? Is ap more accurate than tranverse measurement?

Which test is more accurate in measuring proximal abdominal aorta size in men: ultrasound or mri/mra? Is ap more accurate than tranverse measurement?

Ultrasound: Is the preferred method for screening for abdominal aortic aneurysm as it is less expensive and involves no ionizing radiation. If aortic enlargement is seen, cta is usually chosen to determine most accurately degree of aortic enlargement, extent of aneurysm, and involvement of aortic branches. ...Read more

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What changes a due date? And why is the first trimester ultrasound more accurate than the second trimester ultrasound?

What changes a due date? And why is the first trimester ultrasound more accurate than the second trimester ultrasound?

Ultrasound dating.: First trimester ultrasound is by far the most accurate in determining the precise due date (+/- 3-7 days, depending on exactly when it is performed). Second trimester sonograms are less accurate but still helpful in pegging down the due date within +/-7-12 days. Third trimester scans are not very accurate in dating the pregnancy, as growth varies (+/- 14-21 days). Menstrual dating is not very good. ...Read more

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Embreo transfer or ultrasound is due date more accurate?

Embreo transfer or ultrasound is due date more accurate?

Embryo transfer: Embryo transfer would be the ultimate gold standard for gestation age.The number of days since conception of the transferred embryo (3-5 days) would be known so the precise time of conception would be available so the estimated due date could be more precisely estimated. ...Read more

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How accurate/reliable is a LMP by ultrasound if the patients LMP was unknown?

Pregnant?: I assume you are pregnant. Early transvaginal ultrasound is very accurate and giving a proper gestational age for you pregnancy. From that age a due date is given and an "lmp" date is given even though you may not have actually had a menstrual cycle at that time. ...Read more

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How accurate is the due date with a sonogram at 15w3d?

Usually close. : Studies have shown that up to 20 wks gestation, ultrasound can vary by as much as 1.2 wks. Others have shown a 2 wk variaton between 18 to 28 wks, and 3 wk variation at greater than 28 wks. In a normal developing fetus, variations are usually secondary to the experience and expertise of the technologist, position of the fetus, and the accuracy of the measurements. ...Read more

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Is MRI more accurate than ultrasound test in measuring size of proximal abdominal aorta?If yes or no, why?

Is MRI more accurate than ultrasound test in measuring size of proximal abdominal aorta?If yes or no, why?

No: Ultrasound is very reliable for screening of aortic size, plus it is far less expensive than mri. Mri and ct are better if you are planning surgery on the aorta, as they give far more detail and anatomic information. ...Read more

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What is more accurate in dating conception, going 14 days after the last period, or the ultrasound crown rump?

What is more accurate in dating conception, going 14 days after the last period, or the ultrasound crown rump?

CRL!!!: Due to biological variability in ovulation and implantation/fertilization timing, the use of crl by first trimester ultrasound is more accurate than use of last known menstrual period as dating criterion. In fact, studies have proven that even with certain menstrual dates, the sonographically-determined due date before 20-24 weeks is more accurate for clinical purposes (see jason gardosi's papers). ...Read more

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What is more accurate? Transvaginal us, or pelvic us?

What is more accurate? Transvaginal us, or pelvic us?

Depends: both types of pelvic ultrasound approaches are useful and which is better depends on what part of the pelvis is to be examined and often the body size and shape of the patient. Many clinics do both if they are indicated based on the clinical question requested by the ordering doctor. ...Read more

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