spacefem.com

Length of pregnancy by week

[ Survey Results Intro | All Charts | Take the survey ]

This graph groups the births by weeks. For instance, "week 40" means days 280-286.

Summary

Excluding inductions, here are the percentages for each week: These percentages are based on the 6700 babies born spontaneously, excluding the 2127 babies who were induced. As with the graph, "at 40 weeks" means babies born on 40 weeks, 0 days through 40 weeks, 6 days.

Data Table

Total births: 8827
WeekAll births% of totalRunning total %Spontaneous% of totalRunning total %
351271.41.4 1021.21.2
362482.84.2 1972.23.4
375696.410.6 43958.4
38117813.323.9 93210.619
39218224.748.6 171819.538.5
40259329.478 208123.662.1
41162518.496.4 108512.374.4
422923.399.7 1371.676
43130.199.8 90.176.1
The "running total %" basically tells you how many babies have been born by the end of the week. For example, 38.5% of women went into labor spontaneously before they hit week 40.

Due Date Survey Data

Due 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?
Birth Stories
Survey input dates

More Resources

Pregnancy Day-by-Day
Fast pregnancy calendar
Baby age calendar
EDD Icon Generator
Jo's Birth Story
Weeks vs. Months Explained
Charts generated by flot
spacefem.com
spacefem@spacefem.com

Recent Comments

For more support, encouragement, Q&A,
you are invited to join our pregnancy forum. We are dedicated to answering complicated questions as logically as we possibly can.

What the Hell just entered my earhole?

Tue Aug 4 3:18 AM by DarkOne in Pregnancy & Parenting

Hehe. My story is not nearly as clever, but I had to defend myself against my toddler a few weeks ago:

I was driving around town and came to this intersection with a flashing yellow light in my direction and a flashing red for the crossing traffic. It caught me a bit off guard so I instinctively slammed the brakes for a second before letting go... And then I hear from the back seat from my kid not yet 2: "mommy almost crashed *giggles*"... :mad: EXCUSE ME? No, child, we did NOT almost crash. My driving is perfectly adequate. :mad:


What new thing did your baby do this week?

Sun Aug 2 6:00 PM by rosefox in Pregnancy & Parenting

Mazel tov, annesik! That is a very important milestone! :D


teething necklaces

Thu Jul 30 11:41 AM by DarkOne in Pregnancy & Parenting

A few of the more enterprising/crafty moms in my old parent group got together with a group of friends and bought beads in bulk from alibaba or some other site like that. Some sold the necklaces locally, some made really affordable gifts for friends; I almost jumped in, because a couple of years ago these were still hovering at the $30 mark, but at ~$15, they're much more affordable now, methinks.

They babies I witnessed munching on these were really going to town on them, too.


for all you moms and future moms

Tue Jul 21 2:28 AM by DarkOne in Pregnancy & Parenting

Eek and here I was about to say this felt like a tame version of Mother Lover.


Spacefem's homemade playdoh recipe

Mon Jul 13 3:01 AM by Zeph in Pregnancy & Parenting

A parent in my Kindergarten class would bring us homemade purple play dough that smelled like grape!


Kids books we hate

Mon Aug 3 1:10 PM by Sonic# in Pregnancy & Parenting

I absolutely loved at least one of the Berenstain Bears books (one based off of the Tortoise and the Hare), but I also hate at least one of them. The Berenstain Bears and the Trouble With Chores features a Mama Bear exasperated that no one is doing chores, with the kid bears and Papa Bear keep excusing themselves out of doing them. Rather than coming to some equitable distribution of labor by the end, the house gets really bad and the kids and pop finally binge clean. The situation didn't seem solved; Mama Bear just seemed pacified.


RIE parenting

Sat Aug 1 2:09 AM by ohbonobogirl in Pregnancy & Parenting

I encountered this randomly the other day. Now I need to go dig some more into it...


Braxton Hicks questions

Mon Jul 27 2:13 PM by Metcodon1 in Pregnancy & Parenting

In my experience "real" contractions are pretty much the whole uterus (top, bottom and lower back). I remember reading somewhere that the ones that get you dilated from 0-7/8 cm are largely the muscles pulling up, trying to stretch the cervix out. As a result many people largely do feel them most strongly at the top of their belly. Whether you feel them strongly in your back or not depends on how the baby is positioned. If you've heard the term "back labor" that usually happens if the back of the baby's head is pressed up against your spine (less common than when the baby's face is on the spine). The contractions that take you from 7 or 8 cm to 10 - i.e. the ones in the part of labor known as "transition" - do tend to be lower down (and also more painful). That said, I think there is A LOT of variation in experience...


the wonder weeks: practical help for parents or self-fulfilling quackery?

Mon Jul 20 2:29 AM by geerlady in Pregnancy & Parenting

I am actually a big fan of the wonder weeks. I found it better than most popular level books looking at infant development. My son was right on the clock for the fussy/happy times, and it was interesting to look for the new skills that I might not have noticed if I hadn't been watching for them.

On the other hand, I stumbled upon this accidentally, so didn't have any hype surrounding it. I also read the author biographies before picking up the book, so took everything with a grain of salt knowing that 1) the authors specialized in chimpanzees, not humans, and developed their theories based on chimps; 2) the bulk of the research is greater than 20 years old and so much of the book is out-dated; and 3) given #'s 1&2, incidental parenting advice had to be filtered.

That said, I still found the book useful and regularly recommend it to people.


Pregnancy insomnia

Thu Jun 25 9:05 AM by Gnarlbanya in Pregnancy & Parenting

Thanks for the tips. It's not so much getting to sleep that's the problem, it's staying that way that is causing the issue - too many things waking me up. I seem to be in a bit of a pattern now of alternating good and bad nights, which I guess I can live with. Meanwhile, Netflix is getting a damn good workout in the early hours.


let's list our favorite children's books

Mon Aug 3 1:09 AM by ladyhawk in Pregnancy & Parenting

I loved The Stinky Cheese Man as a child, and my four year old loves it now, but looking at those illustrations as an adult...*shudders*

https://inhyndsight.files.wordpress.com/2013/07/c02af8c76f656c562d5397751a98bf02.jpg

That's the stuff of nightmares, right there.


Newborns are difficult!

Sat Aug 1 2:03 AM by ohbonobogirl in Pregnancy & Parenting

Yay for better, if not yet great. The pacifier has been wonderful for my little creature. I was hesitant to use it, just like you, but it calms him like nothing else and he still eats like a champ. Best wishes!


do you have a parenting goal?

Sun Jul 26 5:16 PM by rosefox in Pregnancy & Parenting

I'm definitely in the "happy healthy child is my only goal" camp. I know some people who are superstars in their chosen fields. From what I can tell, being a superstar is completely exhausting and often really psychologically taxing. So if my kid isn't naturally inclined that way, I certainly don't intend to push them.

If I'm hoping for anything, I hope they'll end up being a quirky artsy/techy type like just about everyone else in the family. But my brother's a corporate lawyer and I love him anyway, so even if our kid turns out to be a white sheep, they'll just bond with Uncle A and it'll all be fine. :)


Diaper bags

Wed Jul 15 3:46 AM by geerlady in Pregnancy & Parenting

We used/still use our diaper bag quite a lot.

For our little guy's first year of life we were urban dwellers and I would often go out for half a day at a time. I would take a diaper for every hour I planned to be out of the house plus one, which was too much for the clutch. I needed a change pad, since he was often changed in nasty places, wipes, hand sanitizer (for changes away from running water), Kleenex, and disposal bags. He needed spare clothes, I needed a spare shirt (discovered after an emergency, useful many times afterwards), and it was useful to have a plastic bag for clothes which were victims of a diaper explosion. For longer days out I would bring two spares for him (and did have days where I used both). I would also have a nursing cover and a blanket in there. We also had a stroller cover for napping which was quite handy when we were taking the stroller as opposed to a carrier. And then there was my stuff, like my wallet, phone, lip balm, keys, granola bar, etc... I did pack the camera, and was often glad for it. Nearly all of our first year pics were from our little excursions.


Antidepressants during pregnancy

Thu Jun 25 1:03 AM by Aum in Pregnancy & Parenting

http://www.henriettes-herb.com/blog/pos ... ssion.html

Pre and post-partum depression have similar reasons, physically speaking. Check nutrition first.