pregnancy due date from conception

Doctors calculate pregnancy using a 40-week calendar, though from the date of conception, pregnancy is only 38 weeks long. They go back and start the count on the first day of your last period. This is the way doctors have dated pregnancy for a long time, certainly from before the invention of ultrasounds, because the first day of a period is a noticeable signal and known date, and ovulation is hidden and happens on a date not usually known.

So they base it on your LMP, and 40 weeks later is when you are due. They can change your due date after you have an ultrasound in the early weeks to tell how far along you are by measuring the baby. So it is confusing, but in the end it turns out right.

I say the first guy is the dad bc you are fertal for 7 days and then you ovulate on the 7th day and then from there it takes a few days for implantation to take place which would put you around your estimated conception date. Plus if your estimated conception date was feb 2 and you didn't have sex with the other guy until the 7th-10th there's no way he is the dad!

The first day of my last period was June 7. I had sex on the 18th and 20th and was ovulating around the 21st. I am now pregnant but am wondering if I am 3 Weeks pregnant or 5 Weeks. Due date predictors and various websites say I am five Weeks because the gestational age starts the day of your last menstrual period. This gives me a due date of March 14th which is only 38 Weeks after conception. Shouldn't I be 3 Weeks along with a due date two Weeks later at 40 Weeks after conception?

), and January 5 is the only time you had sex, then that would be considered your conception date. Your due date would be 38 weeks from then. Based on a due date calculator, your due date would be September 28, 2010. Good luck to you.

If her first ultrasound was at 5 weeks, it will be the most reliable for working out a conception date.

So you usually go 40 weeks from conception to get your due date.. so I think its jan. 20th. But that's just what I think!

Now if I count backwards from my due date to my date of conception, it's 40 weeks. And I am positive about both my LMP and my date of conception. Does this mean that my midwife counts differently or is my due date incorrect?

s computer will compute the start point by looking at the size of the embryo, but will still count back the two weeks from the assumed conception, to get to the average day 1 of last period.

But it also assumes a regular 28 day cycle and conception at around the mid point of cycle or day 14. If you count back 38 weeks from due date you should be within a few days of conception date.

Here's what the conception calculator says regarding the due date of November 28. How early in the pregnancy was the ultrasound that gave you the due date? If you really slept with the other guy only at the end of January, he is probably out of range even if you had a later ultrasound. Do you have any way to confirm that it was no later than the end of January that you slept with him?

Due date July 9th...I think my conception was Oct 13th, 17th or 18th..those were the only 3 days we had sex after my period that was from Oct 2nd to Oct 6th...we were def timing since I had a loss on Aug 20th.

Generally the reason something like a conception calculator asks for the birth date or estimated due date is because it assumes the woman got that date from an ultrasound in their first trimester. Conception calculators also can be set to compute from the first day of the last period, for women who didn't have an ultrasound.

Idk if you did an ultrasound yet or was giving a due date but from my calculations you should be due around August 6. If it was the 2nd dude your due date would be around August 20th. I hope this information was helpful..good luck!

And due date oct 1 but we will get a more accurate from my midwife this was my fame doctors estimation

You can ask your doctor for a possible date of conception. But, they will figure it out by using the date of your last period. In other words... a doctor cannot know for sure when you conceived a baby, they can only guess by using tangible signs like the onset of a menstrual period. If your due date is Jan.4th, then they would have based that on a period that started approximately March 28th.

Mine did with this pregnancy (but not my last). Truthfully, I was pretty sure the exact day of conception this time since we were TTC but had been visiting family out of town around that time also. There really was only one day it could have been during that cycle. The doctor said I probably just ovulated earlier than what is average because the fist due date was from my LMP & the adjusted date was from the sonogram. I'm excited though!

GRose is right...the best thing to do is stick with the original due date. The further along you get, the less accurate the EDD based on ultrasound is. For example, when I was pg with my son, I was about 7 months along, and the ultrasound said I was a full six weeks further along than I really was. I knew it wasn't possible, because I had ONE conception date to choose from for several months...lol. And this time, my "real" due date is 08/05/09.

My due date is 8/26/2014 w/ my LMP on 11/13/13. I have used a few of the conception date calendars online and have put in my LMP & it says my due date should be 8/20/2014 which is only 6 days off but anyways. i made a mistake on 12/11/13 & need to make sure there is no way i conceived that day?

I also slept with my boyfriend the ebd of Feb of 2007, and again in March between the time of 16th -19th.I had an ultrasound in May of 2007 that said i was 8 weeks pregnant with a due date of Dec 10, 2007. I want to know if i could have gotten pregnant in Jan or if it is my boyfriends baby. Please help me to get some relief.

So once it calculates that it gives me a whole different due date and date I conceived. Now I tried by putting my due date and it tells me a different day I conceived and my correct weeks of pregnancy. So idk if to go based off the due date. Has anyone had this problem? Thank you.

Okay guys if I had a blood test done on march 3rd it came back positive for pregnancy do you guys think I should be farther along my due date is dec 2 and conception date march 11.

Could this pregnancy still be from July/Aug or is it from Oct conception? Please advise. I have posted in other channels but they advise to use a calculator obviously I know how to calculate but that's not the question here.

No. You didn't get pregnant in October.

Okay so I am pregnant with my 4th child and I have never understood how they calculate how far along you are. It is not possible to be pregnant on the first day of your period so to count day 1 as pregnancy day 1 seems stupid to me. Now my due date and the Dr.'s due date are only different by a day so it shouldn't matter much except that by putting me 2 weeks ahead of my pregnancy by going from my period would put baby 2 weeks ahead in testing and ultrasound.

Did you get the February 13 due date early in the pregnancy from a doctor reading your ultrasound results?

Pregnancy due date from conception

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