In the survey, 35 participants claim to know their exact conception date. This is rare; most due dates are measured from last menstrual period because it's easier to track. But the general question that always comes up is "Would my due date be more accurate if based off the conception date?"
On the main probability chart I found that due dates have about an 8-10 day standard deviation, meaning that the bulk of the babies are dispersed within plus or minus 10 days of their due date.
For this graph, I subtracted each babies birth date from his or her conception date, then added 14 days across the board because that's usually what we do when calculating a due date based on conception.
The standard deviation didn't improve much when compared to all the women in the survey. So bad news... even if you know the second your baby was conceived, your due date won't be any more accurate.
There is a related chart that compares LMP due dates with ultrasound-determined due dates. It also found no noticable difference in standard deviation.
The statistics right now are as follows:
|Day||Week||Births||Running Total||Percent||Running Total %|
|245||35W,0D||0||0||0 %||0 %|
|246||35W,1D||0||0||0 %||0 %|
|247||35W,2D||0||0||0 %||0 %|
|248||35W,3D||0||0||0 %||0 %|
|249||35W,4D||0||0||0 %||0 %|
|250||35W,5D||0||0||0 %||0 %|
|251||35W,6D||0||0||0 %||0 %|
|252||36W,0D||0||0||0 %||0 %|
|253||36W,1D||0||0||0 %||0 %|
|254||36W,2D||0||0||0 %||0 %|
|255||36W,3D||0||0||0 %||0 %|
|256||36W,4D||0||0||0 %||0 %|
|257||36W,5D||0||0||0 %||0 %|
|258||36W,6D||1||1||2.9 %||2.9 %|
|259||37W,0D||0||1||0 %||2.9 %|
|260||37W,1D||1||2||2.9 %||5.7 %|
|261||37W,2D||0||2||0 %||5.7 %|
|262||37W,3D||1||3||2.9 %||8.6 %|
|263||37W,4D||0||3||0 %||8.6 %|
|264||37W,5D||0||3||0 %||8.6 %|
|265||37W,6D||1||4||2.9 %||11.4 %|
|266||38W,0D||0||4||0 %||11.4 %|
|267||38W,1D||0||4||0 %||11.4 %|
|268||38W,2D||2||6||5.7 %||17.1 %|
|269||38W,3D||0||6||0 %||17.1 %|
|270||38W,4D||1||7||2.9 %||20 %|
|271||38W,5D||1||8||2.9 %||22.9 %|
|272||38W,6D||2||10||5.7 %||28.6 %|
|273||39W,0D||0||10||0 %||28.6 %|
|274||39W,1D||0||10||0 %||28.6 %|
|275||39W,2D||0||10||0 %||28.6 %|
|276||39W,3D||2||12||5.7 %||34.3 %|
|277||39W,4D||1||13||2.9 %||37.1 %|
|278||39W,5D||5||18||14.3 %||51.4 %|
|279||39W,6D||0||18||0 %||51.4 %|
|280||40W,0D||0||18||0 %||51.4 %|
|281||40W,1D||1||19||2.9 %||54.3 %|
|282||40W,2D||1||20||2.9 %||57.1 %|
|283||40W,3D||3||23||8.6 %||65.7 %|
|284||40W,4D||1||24||2.9 %||68.6 %|
|285||40W,5D||0||24||0 %||68.6 %|
|286||40W,6D||1||25||2.9 %||71.4 %|
|287||41W,0D||3||28||8.6 %||80 %|
|288||41W,1D||2||30||5.7 %||85.7 %|
|289||41W,2D||2||32||5.7 %||91.4 %|
|290||41W,3D||0||32||0 %||91.4 %|
|291||41W,4D||0||32||0 %||91.4 %|
|292||41W,5D||0||32||0 %||91.4 %|
|293||41W,6D||1||33||2.9 %||94.3 %|
|294||42W,0D||1||34||2.9 %||97.1 %|
|295||42W,1D||1||35||2.9 %||100 %|
|296||42W,2D||0||35||0 %||100 %|
|297||42W,3D||0||35||0 %||100 %|
|298||42W,4D||0||35||0 %||100 %|
|299||42W,5D||0||35||0 %||100 %|
|300||42W,6D||0||35||0 %||100 %|
Due Date Survey DataDue date statistics: A study on the length of pregnancy
Probability of delivery resulting from spontaneous labor after 35 weeks
Probability of delivery within x days of a given date
Length of pregnancy by week
Spontaneous labor and due date determination
Length of pregnancy, comparing subsequent births for individual moms
Length of pregnancy for first time vs. second & third time moms
Length of pregnancy, type of delivery
Gestation vs. Birthweight
Probablity of Induction after a given day
Average day of spontaneous labor vs. age of mother at time of birth
Are more babies born during a full moon?
What's the most common day of the week for babies to be born?
I'm still pregnant at 40W. What's it mean?
Do winter babies arrive later?
What if I know my conception date?
Are boys or girls born later?
Subsequent pregnancy date search
How do inductions bias the due date statistics?
Download the data
Survey input dates
More ResourcesPregnancy Day-by-Day
Fast pregnancy calendar
Baby age calendar
EDD Icon Generator
Jo's Birth Story
Weeks vs. Months Explained
Charts generated by flot
Sonic, I like the way you described the sound a letter makes.
I asked a few early elementary school teachers I know this same question and wanted to share a bit of what they had to say.
They recommended starting with consonant-vowel-consonant words (CVC) with short vowel sounds, and focus on rhyming families (i.e. bat, cat, fat) and even including first consonant changes that don't make real words, like 'gat'. Then later introduce CVC with last letter changes (i.e. bad, bar, bat). They said we could try sight words at the same time and told me to do a search for the Fry sight word list.
After those CVC words aren't a problem, it was suggested to start adding an 'e' at the end of CVC words to change the vowel sound, an the meaning of the words, so introducing long vowels (i.e. cap->cape). Then after all that, we can start adding two consonants together and two vowels together. From there maybe come up with homonyms together, which can be a great way to introduce silent letters (i.e. new, knew).
I would say its very important, because what you learn shapes and molds yours views that make you who you are.
Aum, my partner and I were just discussing this. He was surprised by my taking the hard line that stopping BC or poking holes in condoms or something like that is rape, making the woman a rapist. Which should result in jail time, so she should lose custody, which should go to the father and now he has the choice of keeping the baby or putting them up for adoption.
It's unfortunate that you can't prove such a thing, but hopefully if it was actually taken seriously women would be less likely to do it because it would at least be explicitly called rape.
I understand how the justice system and the family courts would look at it. They see it as the man's sperm made it to the egg so somehow he wasn't protecting himself, he made the choice, yada yada. There's no way to prove that the woman was manipulative, withdrew BC, or "poked holes in the condom" (I think that's unheard of, but anyway).
I topped baby off tonight. He straight up drank 7 ounces of formula after his prunes. If he's an infiltrator, he's eating well for it.
I am still dealing with the fact that your 11 year old is an actual 11 year old.
My father-in-law spends a lot of time with the kid, mostly by choice. I sometimes wish we had more of a schedule, because at the moment, naps and bedtime are the only semi-guaranteed breaks for anyone. My spouse and father-in-law both work from home free-lance, so they don't actually have a schedule for when they need to be left alone, but at least my father-in-law has more warning with jobs scheduled out in advance.
I'm sorry for your loss. Ectopic pregnancies are scary, and I would like to go punch that first doctor in the face for you.
PPD is awful too.
You can continue discussing with him the difference of a boy and a girl. Have him socialize too with the same gender. There's nothing wrong if you have go with opposite sex as long as he understands what/who he is.
So do you feel hanging out with the opposite gender at a young age can confuse a person's gender identity?
If a boy who has a penis asks if he's a boy and you don't just say yes, then that's straight up lunacy.
What he decides to do with that boyhood or how he dresses is up to him. But if you're born with a penis you're a boy.
Making it airy fairy when, statistically, scientifically, less than 1% of 1% of children born have true gender dysphoria, is immoral and wrong. It's also a sign of our troubled times.
This is just my anecdotal experience but...
I have experienced bullying based on simply engaging in normal children's play with girls. Insults were attacks on both me and the girls. But I NEVER questioned my gender as a male. So if a child asks me if he's a boy and was identified biologically as one, I am going to question what influences are on the child before I answer.