The Pregnancy Conception Calculator estimates the date of conception based on the expected due date of the pregnancy, last period date, or ultrasound date. The date of conception is the day on which a person's baby is conceived. The calculator also estimates a possible range of days during which sexual intercourse might have led to conception based on sperm being viable for days within a woman's body. When exactly did I get pregnant? Many women often ask this question when trying to figure out the exact day their pregnancy began. Often, gestational age, or the age of the baby, is calculated from the first day of the mother's last menstrual period. However, in reality, the baby was not conceived until ovulation and the fertilization of the egg, which usually happens at least 10 days after the first day of the mother's menstrual period.
You would never know whether the sperm that fertilised the egg was a slower swimmer from Fri that was laying in wait for your egg being released - or a fast swimmer from Sunday that pipped it to the post! Also, embryos grow at different rates and can implant on different days. So you might think 'the' occasion was Sunday - when in fact it was after fertilisation on Friday but the ebryo took a little longer than average to get going.
And of course - they come when they're ready anyway, so it doesn't make that much difference to your real birth date!
How accurate are dating scans / when did i conceive ?
Who knows. G's EDD was put back 10 days after our dating scan. But babies rarely appear on their due date anyway.
As usual, I've been given some different advice to MarineGirl - why do health professionals never sing from the same hymn sheet?? FWIW I have strange cycles so hard to know conception date but for my last pregnancy, the date they gave me at the 12 week scan was the day on which LO arrived, so I am going by that date again this time!!
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Page 1 of 1 11 items. Locked Contact. Sharrington Posts 12, I would go with your scan.
Determine the most probable conception dates, and explore a number of other on the expected due date of the pregnancy, last period date, or ultrasound date. In cases like these, one of the more accurate ways to estimate gestational age . Use this due date calculator to find out when you're due, how many weeks along Calculating an accurate due date is an important first step in pregnancy. Why does the ultrasound give a different due date from the conception calculator?. Or shall i just go by my due date from dating scan? Then how do i Like Sharrington, I know my dates exactly, because it's an IVF conception.
Vindaloo Posts 26, Scans are pretty accurate. MarineGirl Posts 12, My first was at nearly 14 weeks - so guess i cant really use that then Oh well not to worry - would have been nice to know but not a big deal. Thanks MG. Lady Falafel Posts 16, An obvious fact is you cannot conceive until you ovulate; therefore, the most likely date of conception is on the day of ovulation, if there is sperm around. If you can determine that day, you will come close to identifying your date conception.
There are various ways to estimate the day of ovulation. You can estimate your date of ovulation and conception from the length of your menstrual cycle if this is fairly regular.
I had a ultrasound on April 1st and they said i was 8w3d pregnant with my son. Hey did you ever find out whether the conception date was off by 10days know my last menstrual period and use that for dating my pregnancy. Her first ultrasound was 2/20/, dating her at 12 weeks exactly with an due want to know could the ultrasound predicting conception date be wrong, i know i dont have long before he's born, i just want to know the odds. Ultrasound in early pregnancy (before 12 weeks) – Dating Scan measurement is not absolutely accurate. Instead LMP vs ultrasound for due date calculation.
The most consistent part of the cycle is the second half after you ovulate. No matter how long or short the cycle, you will get your next period around 12 to 14 days later. If you have a consistent day menstrual cycle, you most likely ovulated and conceived on day However, you could have conceived on day 12 or 13 if ovulation was earlier, or days 15 or 16 if later.
How accurate are dating scans to determine conception date
So, by this example you can understand you have a five day window during which you could have conceived. Women who have irregular periods will have a more difficult time determining the date of conception using the menstrual cycle length method.
If you were tracking other signs of fertility, such as basal body temperature chartsor ovulation predictor kitsthey can help you narrow down your conception date to within one to two days. If you were charting increased pain at mid-cycle, the day of the worse pain on one side of your pelvis is the likely day your egg ovulated. This is probably the day you conceived if you had intercourse around that time. An ovulation predictor kit OPK or LH kit reliably predicts the window of ovulation, according to a study published in in Human Reproduction.
The at-home urine test measures the increase in the pituitary luteinizing hormone LH that occurs in the days leading up to ovulation. Your most fertile time to conceive is within the day or two after a positive result.
If you did an LH kit during your conception cycle, take a look at your test results. The day of your definitive positive reading is the day of the biggest increase in your LH.
Use our Pregnancy Calculator to calculate these dates for you. Measuring the baby using ultrasound is most accurate in early pregnancy. Any calculation of a conception date is an estimate, even in a woman with regular day menstrual How accurate is the conception date from an ultrasound?. In order to determine an accurate estimated due date (EDD), your doctor ultrasound measurements in the first 14 weeks of pregnancy are the.
This "LH surge" triggers ovulation and predicts it is likely to occur 24 to 36 hours later. That one to two day window after your surge is the likely time you conceived. If you kept a basal body temperature chart BBT during the cycle you conceived, this is a useful tool to help pinpoint when you ovulated and therefore conceived.How to Calculate Your Due Date by Ultrasound (Week 6-2)
Here are some helpful facts:. Keeping track of cervical mucus changes within a menstrual cycle can help narrow down the day of ovulation. If you tracked these changes, the day before your mucus changed to a thick, tacky, cloudy, dried-up mucus was the day of ovulation, and your likely date of conception.
The day of ovulation, your mucus would have been at its most thin and watery, as well as clear and stretchy like egg white. This is most likely the day you conceived.
You may know when your LMP was, but not when you actually conceived. If you do know the conception date.
Once your doctor or midwife gives you your due date, count 38 weeks back on a calendar to find your most likely conception date. This calculation assumes the following:. An ultrasound is yet another way to help establish a conception date.
There may be some concern as to how accurate the conception date from an ultrasound would be, and it is actually one of the best and most accurate ways to determine when you are likely to conceive.