Question 1

if my first ultrasound said 7weeks and 4 days and my second said 10 weeks and 2 days would be date of conception be accurate? when i put it in a calculator it said 6/19/2021 date of conception?

Accepted Answer

: The expected date of delivery has a leeway or two weeks on either side, so it is not necessary to be so particular about a few days this way or that.

Question 2

i had unprotected sex november 16, 2013 everytime i put that into a online pregnancy calculator under "date of conception" its says im 4 weeks. why?

Accepted Answer

Easier calculation: Every pregnancy dating software is based on a 40 week pregnancy. Actually the pregnancy is not 40 weeks but 38 weeks.  Not every women knows when they conceive but women know when their last menses occurs. Therefore the dating is from the last menses artificially adding 2 weeks to every pregnancy.

Question 3

conception query could someone i had sex with 2 weeks before my partner be the father of my child? due date, all ultrasounds, conception calculators match up to the date me and my partner had intercourse, give or take 2 days?

Accepted Answer

: The only worthwhile answer &amp; one that will hold up in court proceedings will be a DNA based paternity test. The NIPP is a non-invasive test performed on your blood as early as 8 weeks. They find fetal DNA in your blood &amp; can test it for a variety of things including paternity. Ultrasounds and projected dates can give data, but a surprise at delivery is not worth a wrong call.

Question 4

how accurate are ultrasounds for dating pregnancy what's the margin of error. if my due date is oct 31, what are the dates i could have gotten pregnant?

Accepted Answer

What year?: It would seem that you would have to conceive on feb.. 8, 2014 to give birth on 10/31. If the question is of historical interest, i would need to know when the ultrasound was done. Otherwise, you might want to check the dates you provided.

Question 5

can longer implantation time affect dating ultrasounds in early pregnancy?can it affect growth estimates in early pregnancy and date you behind?

Accepted Answer

Yes: This usually does not affect the dating more than a few days.  If you keep track of ovulation, that would help your Provider give you a more accurate date.

Question 6

how find out expected date of pregnanacy by using ultrasound?

Accepted Answer

Standard measures: This is a complicated topic and dependent on how far along you are. Ask the doctor who will be performing your ultrasound.

Question 7

accuracy at 11wks. pregnant, going by the actual age of pregnancy can it be possible for the ulstrasound to date me 10 days before i even had sex with second partner and 1 day after my first partner?

Accepted Answer

: Evidence suggests that ultrasounds more accurately predict your due date than using your last menstrual period—but only in the first trimester and early second trimester (until roughly 20 weeks). Early ultrasound due dates have a margin of error of roughly 1.2 weeks. After 20 weeks, your Dr will measure your fundal height to see if the baby's growth is keeping on track with the EDD.

Question 8

why would an ob change your due date from an ultra sound taken at 9 weeks of pregnancy but not mention until 3 days beore said due date?

Accepted Answer

Common: Bonnie, it is very common to revise the due date based on ultrasound evidence, because it is much more accurate than the first day of your last period. Why they didn't mention it earlier, I can't say, but remember that guessing a due date is an inexact science. Only 5% of babies are actually born on their due date. Hope this helps!

Question 9

my first sonogram of 8 weeks and 2 days of pregnancy says my due date is sept.17, 2013. could i have conceived between dec.15 and dec.26 of 2012?

Accepted Answer

Around xmas: If you estimated due date on 09/17/2013 that  makes  your LMP around 12/11/2012 , usually you get pregnant about 2 weeks after your period so most likely  you conceived around xmas  12/25.

Question 10

are conception calculators accurate based off first ultrasound?

Accepted Answer

: Conception determined by "first U/S" are approximate, and do not accurately determine the actual "due date" or ovulation date, as ovulation may be often delayed, and the U/S only measures correlation of fetal dimensions with estimated fetal age, but size and growth rate variations distort the accuracy of either due date or last ovulation.

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Doctor answers about:

Pregnancy calculator by ultrasound date

A member asked:

If my first ultrasound said 7weeks and 4 days and my second said 10 weeks and 2 days would be date of conception be accurate? when i put it in a calculator it said 6/19/2021 date of conception?

A member asked:

I had unprotected sex november 16, 2013 everytime i put that into a online pregnancy calculator under "date of conception" its says im 4 weeks. why?

A member asked:

Conception query could someone i had sex with 2 weeks before my partner be the father of my child? due date, all ultrasounds, conception calculators match up to the date me and my partner had intercourse, give or take 2 days?

A member asked:

How accurate are ultrasounds for dating pregnancy what's the margin of error. if my due date is oct 31, what are the dates i could have gotten pregnant?

A member asked:

Can longer implantation time affect dating ultrasounds in early pregnancy?can it affect growth estimates in early pregnancy and date you behind?

A member asked:

How find out expected date of pregnanacy by using ultrasound?

A member asked:

Accuracy at 11wks. pregnant, going by the actual age of pregnancy can it be possible for the ulstrasound to date me 10 days before i even had sex with second partner and 1 day after my first partner?

A member asked:

Why would an ob change your due date from an ultra sound taken at 9 weeks of pregnancy but not mention until 3 days beore said due date?

A member asked:

My first sonogram of 8 weeks and 2 days of pregnancy says my due date is sept.17, 2013. could i have conceived between dec.15 and dec.26 of 2012?

A member asked:

Are conception calculators accurate based off first ultrasound?

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