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They are accurate within 2 or 3 days. But this does not mean that you will have the baby on your due date. Babies can be born any time between 37 and 42 weeks. That is what midwives are taught anyway. With my first my ultrasound said I was due 10 days after my period date but my husband had been away on a trip form the day after conception! Second time around the ultrasound agreed completely, and showed twins. (now 16) == Your last known period date or the date of conception is a better all babies are different & you may have an extrememly large or an extremely small baby for it's gestational age, and when compared against babies in the "norm" the due date could be way off.

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โˆ™ 2008-03-15 07:45:10
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Q: How accurate are due dates predicted by ultrasounds?
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Are ultrasounds accurate when you do remember your last period?

Yes, I remember my last cycle and I estimated my own due date to be Aug.8 well when I had my ultra sound it said Aug.5 so if not very accurate its very close... Good luck.

How accurate is an ultrasound if you do not remember your period?

If you do not remember the date of your last period you can have an ultrasound to determine your due date. More than one ultrasound throughout your pregnancy may be required because ultrasounds are not always accurate. They could be out as little as a couple of days by a matter of weeks.

How much can due dates be wrong by?

It all depends. If you're doctor is going by the date of your last menstrual period, and you have irregular ones, then it could be quite a bit off. Also, implantation bleeding can be mistaken for a period as well. Ultrasounds in early pregnancy are accurate to a week or so. And a due date is just an estimate. Only 10 percent of women actually deliver on their due date.

How do I know my accurate due date when based on my period it would be Jan 10 but an ultrasound says Jan 14?

ultrasounds are a better judge, in an ultasound it measures the baby to see how big it is and then it is fed into a chart that will tell you when the due date is, the chart is based off of what size the baby should be at that week and day.

Which apps can I use as a due date calendar?

Due dates are predicted based on your menstrual cycle so be sure to know when your last period was prior to using the calculator. WebMD will explain the formula for you.

How accurate is 10 and 12 week ultrasound had 2 that coincided with each other the 10 week 2 weeks later the 12 week and they added up can ultrasounds be off by 4-5weeks?

I have been doing a lot of research on the early ultrasounds. I have a 4 1/2 year old, she was born a day before her given due date. I had an early scan with her. I am now 25 weeks pregnant. I had an 8 week scan and from my research i have gathered that the early ultrasounds are very accurate. there is no mistake between a 7, 8, 9 10, week fetus. They all grow at the same rate until around 12 weeks or more. The best way to tell if your due date is accurate is to see how the dates match up with later ultrasounds. I had one at 8 weeks, 10 weeks and 19 weeks. My due dates added up within +/- 3 or 4 days. I was told that based on my 8 weeks scan i was due august 12th and i conceived on the 20th of November GIVE OR TAKE 3 DAYS. all of my dates have added up so far so i would trust the early scan you had. The only reason a scan might be off considerably would be due to an abnormality or a problem with the babys growth development. I would have to say that no, an early scan would never be off by 4 to 5 weeks unless the baby had died and it was a missed miscarriage but that would be very noticeable as well. so i would say it is almost impossible for a scan to be off by that much, I'm sure it has happened though! life is funny that way. I hope this helped

How accurate are the fetal measurements in determining you due date?

They are almost accurate. I was told my baby girl was due on 9th March. She came on the 7th, but looked at least 1-2 weeks overdue. I knew when my last menstrual period was but according to the ultrasound dates it was different. I would say in some cases they are pretty accurate, but if you know when your last menstrual period was and when you had sex, your dates are better then the doctors.

How long was Eiffel predicted to stand for?

actually it is due to fall down tommorrow

Is it possible to be further along in your pregnancy than what your ultrasound says?

When they do an ultrasound, they measure the baby's head and that's how they determine how far along you are. So if your baby's head is smaller than average, then they would give you a farther due date; If it's bigger than average they would give you a closer due date. Please remember your due date is an estimated guess, not the actual date you will absolutely deliver It depends how much the difference is and at what stage you have the ultrasound. At six weeks ultrasounds are accurate to within 2-3 days, by 12 weeks they are accurate to within 4-5 days and by 20 weeks they are only accurate within 5-7 days.

Is it possible for the ultrasound to be off by two weeks during the early stage?

well anything is possible, but this is science. Ultrasounds are very accurate in the begining maybe 1 or 2 days, but not 2 weeks. FInd out you're due date and go check out and they can calculate you're date of conception for you for free. God bless

How Weather forecasts are more accurate today than in the past due to?

Weather forecasts are more accurate today than in the past due to the use of images from space.

How accurately can an ultrasound determine the date of conception?

Ultrasounds measure the size of the fetus to predict a due date and are usually very accurate, within two weeks, so I would safely assume that it would not be off by five weeks. You can ask your doctor, it won't be the first time he or she has answered that question,I promise. Also it depends on when the U/S is. U/S before 12 weeks of pregnancy are very accurate, plus or minus 2 weeks. After that there are more varibles, babies grow at different rates so they are not as accurate.

Can you get an accurate due date from vaginal ultrasound at 5 weeks?

You could but keep in mind that it could also very much change depending on how the baby is measuring at the midway ultrasound. Even then the due dates are just estimates!

Can a ultrasound be accurate if its saying im now due 3 weeks later then they determined?

Can a ultrasound be accurate if its saying im now due 3 weeks later then they determined?

There is a 12 day difference in due dates ultrasound confirms an earlier date and LMP is a later date Which is more accurate?

I go by the LMP, but even then I had mine early.

What day did you conceive im due April 21st 2010?

Possibly 15th July 2009. Due dates arent always 100% accurate but can give you a rough estimate of when you could expect the delivery of your baby and calculate when you may have concieved.

What is a synonym for expected?

anticipated, proposed, predictable, due, likely, coming, awaited, foreseen, hoped for, looked for, predicted

What is the synonym for expected?

anticipated, proposed, predictable, due, likely, coming, awaited, foreseen, hoped for, looked for, predicted

When is coal due to run out?

Coal resources are predicted to last at least 250 years at the current use rate

What was the discovery of neptune due to?

Mathematical calculations to explain an anomaly in the orbit of Uranus. predicted it existence before it was seen.

Would a home pregnancy test be accurate if you're not due to get your period for another two weeks?

It would probably not be accurate since it is testing for the hormone HCG and you should wait until your period is due in anther 2 weeks to test again for accurate results

Why does water have a higher boiling point than predicted?

The hydrogen bonds between water molecules are sufficiently strong.

Which is more accurate the ancient seismograph or the modern seismograph?

The modern seismograph is much more accurate due to technological advancements and progress in Science

How can you be sure that a website is accurate?

If it was created by a governmental agency, chances are it is accurate due to the fact that the government can't legally release false information.

Do doctors give ultrasounds at 6weeks?

Yes they do usually if you have irregular periods so they can give you a due date. Normally you will get you're first one when you're baby is 12 weeks. GOOD LUCK