Question 1

confused! my due date doesn't add up with date of intercourse or cycle. if i'm due aug 17th, when did pregnancy start? intercourse and conception?

Accepted Answer

Online calculator: Use a reverse due date calculator for free online and this will be easy for you to find out. Simply type in your due date and the conception date will be calculated for you.

Question 2

so if on july 28th an ultrasound dated a pregnancy 7w4d and then on august 16 an ultrasound 10w2d when was conception? her period was supposedly 6/5/2021 or 6/6/2021 due date march 12th 2022?

Accepted Answer

: Ultrasounds, especially early in pregnancy cannot be relied onto determine conception date or actual fetal age. They are used to estimate these points, detect any unusual findings and plan for delivery. At the infants delivery there is a better chance of providing a range of possible conception dates when actual physical findings on the infant define the length of the pregnancy in weeks.

Question 3

when is pregnancy calculated first day of last period or conception because my lmp is 9-8 40 weeks from that would give me a due date of 6/15?

Accepted Answer

40 weeks from LMP: 40 complete weeks from the first day of the last normal mentrual period. With uncertain lmp, dating is  by ultrasound, but if within 1 week to lmp, then menstrual dating is still used. Obstetrical dating is never based on conception, even with ivf pregnancies.

Question 4

i had sex dec 27-jan1, had a one night stand on the 5th and took a plan b pill. lmp dec9 due date sept27 vomiting jan 10. maybe pregnancy signs what re all posible conception dates?  was i preg alredy

Accepted Answer

Jan 4: Your LMP and due date don't coincide, so I assume your dates were changed by an ultrasound. That means conception occurred Jan 4. However, if the ultrasound was in the first trimester, it is accurate within 4-5 days. Therefore, the conception date could be 4-4 days before or after. If you are concerned about paternity, you will need to have the baby tested after birth.

Question 5

i spotted on sunday into monday period was due on the 29. i took. pregnancy test last night and yes they were positive but when would i have ovulated if i implanted due date of my period? had sex 11,14,15&22. when was conception

Accepted Answer

What do you know?: "What you know" will give you the answer. For example, if a woman knows her LMP (the start of her last period) and she knows she ovulates about 14 days after that, then her estimated date of conception will be about 14-19 days after her LMP. If she never really knows her ovulation dates, then we simply label whatever day is 2 weeks after her LMP as her conception day. Dates are always estimates.

Question 6

if i didnnt have periods for to yrs due to depo-provera how can they date my pregnancy off lmp. edd based on 1st u/s at 14w was it based off lmp or conception?

Accepted Answer

U/s dates from size: Pregnancy due dates can come from actual dates of last menstrual period LMP which estimates a conception date of 2 weeks later.  Due dates from ultrasounds come from the measurements taken during the ultrasound.  Sometimes it is used to estimate when conception took place but at 14wks is possibly up to a week off +/-.  Hope that helps and congratulations.

Question 7

had sex on september 27th and october 5th, due date is june 22nd, lmp was september 19th.. what is my date of conception? due date based off early u/s

Accepted Answer

Too close to call: If sex is with one person (monogamous), the dates shouldn't matter. If not monogamous, a woman should keep different guys at least two (2) weeks apart, in order to figure out who's the daddy. Otherwise, it is "too close to call". An old-fashioned way has worked for thousands of years (the husband of the woman is the father). The new way works too (doing a DNA test on the baby and one of the men).

Question 8

if due date was june 3 based on lmp of aug 27, then it changed to may 31 after u/s, could this be bcuz i ovulated sooner? conception date different?

Accepted Answer

Yes to both. : Is very common to have the due date changed based on the findings at ultrasound. It is often around a month off because it is frequently such that one does not ovulate when they thought they did, but actually ovulated the previous month or in fact a later month. So your findings are common and should be believed because the early ultrasound is extremely accurate.

Question 9

explain due date based on date of conception?

Accepted Answer

Due date: The normal term pregnancy last 40 weeks. This is calculated from the last menstrual cycle. The last menstrual cycle calculation relies upon the fact that ovulation occurred on day 14. But if calculations are from the date of conception then the pregnancy is only 38 weeks.

Question 10

if my estimated conception date is june 19th based on the sonogram due date, what is the likelihood of that being a result of sex on june 9th?

Accepted Answer

Not likely: Sperm normally doesn't survive in the cervical mucus for more than 24 to 72 hours, so it is unlikely that the conception date is june 9. Unless the ultrasound dating is in the third trimester then the accuracy is plus or minus approximately 2 weeks.

Get Virtual Care

For Businesses

About Us

HealthTap Online Primary Care Doctors Accepting New Patients

Doctor answers about:

Pregnancy due dates based on conception

A member asked:

Confused! my due date doesn't add up with date of intercourse or cycle. if i'm due aug 17th, when did pregnancy start? intercourse and conception?

A member asked:

So if on july 28th an ultrasound dated a pregnancy 7w4d and then on august 16 an ultrasound 10w2d when was conception? her period was supposedly 6/5/2021 or 6/6/2021 due date march 12th 2022?

A member asked:

When is pregnancy calculated first day of last period or conception because my lmp is 9-8 40 weeks from that would give me a due date of 6/15?

A member asked:

I had sex dec 27-jan1, had a one night stand on the 5th and took a plan b pill. lmp dec9 due date sept27 vomiting jan 10. maybe pregnancy signs what re all posible conception dates? was i preg alredy

A member asked:

I spotted on sunday into monday period was due on the 29. i took. pregnancy test last night and yes they were positive but when would i have ovulated if i implanted due date of my period? had sex 11,14,15&22. when was conception

A member asked:

If i didnnt have periods for to yrs due to depo-provera how can they date my pregnancy off lmp. edd based on 1st u/s at 14w was it based off lmp or conception?

A member asked:

Had sex on september 27th and october 5th, due date is june 22nd, lmp was september 19th.. what is my date of conception? due date based off early u/s

A member asked:

If due date was june 3 based on lmp of aug 27, then it changed to may 31 after u/s, could this be bcuz i ovulated sooner? conception date different?

A member asked:

Explain due date based on date of conception?

A member asked:

If my estimated conception date is june 19th based on the sonogram due date, what is the likelihood of that being a result of sex on june 9th?

HealthTap Online Primary Care Doctors Accepting New Patients

Telemedicine

Primary Care

Manage Your Conditions

Women's Health

Children's Health

Men's Health

Senior Health

Wellness, Prevention & Lifestyle

Sexual Health

Mental & Behavioral Health

Travel Medicine

Urgent Care

Didn't find what you're looking for?

More of what we treat

Allergies

Antibiotics

Asthma

High Blood Pressure

Prescriptions

Type 2 Diabetes

For Businesses

Company

Health Content

Join Us

Download HealthTap

Questions?