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Your due date is calculated by the first day of your last regulare menstrual period the doctor will give you an estimated due date according to the chart that they have which is calculated to 40 weeks....the ultrasound will give you an estimated due date according to your LMP and fetal development if the fetus looks under or overdeveloped for when your saying your LMP was then your doctor will consult you and maybe run some more tests but all EDD are to 40 weeks although remember they give you a 2 week margin meaning you could go at 38 or 42 weeks hope this helps Good Luck and God Bless!!!

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โˆ™ 2006-04-09 17:35:10
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Q: Is the due date on an ultrasound calculated on 40 weeks or 38 weeks?
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When you go for a ultrasound and the doctor tells you that you are twenty weeks does that mean you conceived twenty weeks ago?

No. Your due date is calculated from two weeks before actual conception. You are actually pregnant for 38 weeks. You conceived 18 weeks ago.

7 weeks 3 days pregnant by ultrasound what is the due date?

hi Im also 7 weeks and 3 days DUE date is about in JULY 1

Your due date was July 21 2007 and you had your baby July 23 2007 you got your due date from your first ultrasound at 10 weeks How accurate was this ultrasound and when did you conceive?

Two days late is perfectly normal. A date by ultrasound is only an estimate.

When an ultrasound gives me an estimated due date do i count back forty weeks to get an estimated conception date?

No, you count back 38 weeks for the conception date, but don't forget this is just an estimate.

How do you figure out pregnancy due date?

Your pregnancy due date is calculated from the FIRST day of your last menstrual period. Starting from this day, count 40 weeks forward and that is your due date. This is the typical method used in OB/GYN offices and is the standard way to calculate due date. If the date of you last menstrual period (LMP) is not known, doctors can also estimate a due date based on an ultrasound measurements of the fetus.

Can you calculate what day you got pregnant from your due date?

The due date is calculated from the first day of the last menstrual period. It can also be calculated based on an early ultrasound. If you have an accurate due date, you can estimate the day of conception by counting back 38 weeks. SInce not all women ovulate on day 14 of their cycle, and stay fertile for 2-3 days after ovulation, this result will be +/- about a week.

My due date with the ultrasound is June 9 2008 at ultrasound don't Nov 7 2007 they said I was 9 weeks two day when did I conceive?


How can you work out your due date if your last period lasted for 3 weeks?

I think you are going to have to go with the ultrasound on this one.

Why would the Fetus measuring small on ultrasound Is there anything to be worried about when my due date is Feb. 17 and ultrasound is saying the fetus measures for a due date of Feb. 27?

That's only a 10 day difference. The doctor may have just miscalculated the due date. Your due date is 40 weeks from the first day of your last period.

How many days out could a scan be?

An obstetrical ultrasound can be as much as 1-2 weeks off, before or after the due date.

If an ultrasound at 14 weeks showed your due date as Oct 2 and an ultrasound at 20 weeks showed the same but a 28-week scan gave a Sept 23 due date could you have conceived before Dec 12?

Absolutely not. The later in pregnancy the less accurate the scan. The first two giving a due date of October 2nd will be correct and give you a conception date of around January 9th.

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!

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.

If your due date from your period differs from your ultrasound due date does that mean high risk of miscarriage?

No, it does not mean that you are in high risk of a misscarriage. The Doctor will normally give a due date with an ultrasound but with a variable of 2 weeks before or after the due date. No worries! Thank you! I also did some other research, and i guess since I just came off the pill, that could have thrown off my ovulation for that month, which could throw off my due date.

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?

If my ultrasound said you were 6 weeks 5 days pregnant on April 12 2008 What day did you conceive?

Conception dates can be worked out from the due can send me a message with your due date and I can work it out for you if you want?

When did you conceive if you gave birth on April 6?

It is impossible to say as a term baby could be born from 37 weeks to 42 weeks of pregnancy. You need a due date from a period or an ultrasound to have an idea of conception date

Why do an ultrasound at 12 weeks?

Ultrasounds are usually done at 12 weeks to date a pregnancy, and give you a due date. Aslo to make sure the babys measurements are fine and that the baby is growing right. Good luck

Your ultrasound showed that you are 6 weeks pregnant but you should be 9 could that mean you are having a miscarriage?

An ultrasound at 6 weeks should show a fetal heartbeat, if there was a fetal heartbeat you're not miscarrying.. It's probable you estimated your due date wrong.

If an ultrasound at seven weeks on October 25 predicts a due date of June 3 when did you conceive?

When the doctor counts you as 7 weeks, they are counting from your last period. I figured if the ultrasound says 7 weeks, that is from around sep. 7th, the 1st day of your last period. meaning between sep. 18th thru sep. 24th could have got you pregnant. Likely the 21st. However an ultrasound of 7 weeks on 25th October gives you a due date of 13th June not the 3rd. See the Related Link for "conception-calculator" to the right for more.

At 34 weeks pregnant and they did your first ultrasound at 9 weeks but your not sure if your period date was right can they still tell you accurately when your due date is.?

most of the time at that point the dr can tell how far along you are by your size and size of the baby, but they could be wrong it happens all the time. if they do another ultrasound it will be accurate. with my daughter i had implantation bleeding , i knew it was because it was early and very light and only lasted a day. but the dr set my due date with that counting as my last "normal " period. i knew she was wrong so i calculated it myself and i was right! i went into labor the day i had calculated my due date to be. sorry this is long i do have a point:) if you think the dr went by the wrong period time, keep his due date in mind, but also recalculate from when you think you got pregnant. maybe youll be lucky and your real due date will be earlier than you thought! good luck! hope this helps!

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.

When did you conceive if your due date is June 26 2012?

I think its around the 4th October - this is also my due date from first ultrasound at 9 weeks, and i think they date back from last period which is 20th Sept, 2011 - and if you check with the due date calculators online they give an estimated date of conception of around the 4th October

When was conception date if due date by ultrasound is 1 of Sept?

November 24, 2011

What does a pelvic ultrasound reveal about a fetus?

In early pregnancy (about five to seven weeks), ultrasound may determine the size of the fetus to confirm the suspected due date, detect multiple fetuses, or confirm that the fetus is alive (viable).