Are more babies born during a full moon?

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It was silly of me to make this graph because multiple large-scale studies have shown that there is no correlation between the phase of the moon and when babies decide to show up. But when you're a programmer with data and a word problem, sometimes bad things happen.

This graph looks pretty even, so I'm going to conclude the same thing everyone else does: babies don't care anything about what the moon's doing, they come when they're ready to be born.

Math check

I like showing my work, so here's php code to figure out what moon phase a recent date is in. This also inspired me to write my What moon phase were you born in quiz, there are more notes on moon phases and lunar months then.
// Start with the date you're learning about ($timestamp)

$synmonth = 29.53059;	// Days in a synodic lunar month
$oneday = 24*60*60;	// Seconds in a day
$firstnew = mktime(12,0,0,1,26,1971);	// We happen to know there was a new moon on 26 Jan 1971

$timestamp = $timestamp-$firstnew; // Difference between our timestamp and the new moon

$daysoff = round(fmod($timestamp,$synmonth*$oneday)/$oneday,0);

Data table

Days away from
the new moon
# of babies
spontaneously born
0111
1280
2294
3268
4287
5259
6275
7255
8302
9276
10268
11249
12277
13260
14253
15251
16294
17251
18220
19260
20286
21256
22281
23261
24264
25247
26256
27281
28279
29260
3012

Due Date Survey Data

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Length of pregnancy, type of delivery
Gestation vs. Birthweight
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More Resources

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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.

spacefem's guide to baby-led weaning

Fri Feb 5 8:25 PM by melsbells in Pregnancy & Parenting

^What "weaning" means varies regionally. I've encountered it to mean stopping breastfeeding, introducing solids, or the whole process from solely consuming milk to solely consuming table food.

I fist heard of this when one of my friends had a baby and the rest of us were saying things like "we could see you making your own baby food" to which she replied that she did, but not they way we were thinking of it. When I was pregant, I was asking my friends who went before me lots of advice questions, and I was sold on baby-led weaning, for all of the reasons Spacefem mentioned. I like not having to read ingredient lists, but that goes along with "laziness".

We didn't take things slowly when introducing foods, but we did write everything down, which would have been helpful if an alergic reaction did take place. We offered various raw foods grated, like carrot, and always gave fruit raw (not grated). We eat a decent amount of strongly spiced food and take out our kid's portion before adding the more intense flavors or heat, but their food has been getting spicier over time.


the unplanned homebirth

Tue Feb 2 11:37 AM by Aum in Pregnancy & Parenting

My great aunt had a baby while on the toilet... but then, she had 19 children in total so I'm sure by baby 10 it wasn't that big of a deal.


High needs newborn support thread

Fri Jan 8 5:12 PM by rowan in Pregnancy & Parenting

One thing I do now that I wish I had done earlier on (though not sure I could have done in the first 6 months due to brain fog), is if I find myself thinking "I wish I could do X" or "I wish I had time for..." even if it's a fleeting thought, I write it down. Well actually I put it in my toodledo list, which I can access on my phone/computer/wherever. Then when I find time I'm like soooo what do I do again? Oh yeah! I wanted to do this thing! I mean, as simple as "read book" or "bake a thing" or something.

Early on though it might be good to look at the list though. Just add things to it. Eventually it gets better and time will come back.


How many sheets/clothes/blankets etc for newborn?

Tue Dec 29 4:41 PM by rowan in Pregnancy & Parenting

^This reminded me, we got two receiving blankets that were made for us, and they were bigger than the little ones that people buy. THOSE were way more useful for much longer.


Vent, advice: How to not be crazy at work...or in general

Wed Nov 4 3:23 PM by Maro in Pregnancy & Parenting

So, my pregnancy hormones are causing me major mood swings right now. I don't necessarily feel ashamed of it, but I'm frustrated enormously by it because I've got a ton of projects at work and a two-year-old to deal with, and I honestly do not have time to sit and cry for 30 minutes every few hours. I really hate being pregnant, for that and other reasons, but right now it's mostly that.

This morning I felt awesome and totally zen and amazing and only vaguely nauseated, and then a couple of things hit at work that I routinely eat for goddamn BREAKFAST and I'm a puddle of tears in my office. Luckily, I work from home so no one can see me, and all I can really do is push through it and keep getting stuff done. But it majorly sucked. Maybe there's no way around it...but if anyone has any ideas for coping with this stuff I'd be grateful. When you Google pregnancy hormones and mood swings the majority of advice is aimed at husbands "surviving" it, which immediately sends me into a rage spiral.


The pregnant woman's business trip from hell (or at least heck)

Fri Feb 5 5:24 PM by trillianastra in Pregnancy & Parenting

Wow, lyra211, that's really interesting information. So it sounds like she wasn't just screwing up mildly--she may have actually been reacting medically inappropriately. I'm glad it's (so far) worked out fine, but I definitely need to talk to the doc about this. :mad: :bomb:

I guess it's somewhat common for more seasoned medical professionals to rely on the information they got in their initial training, but isn't that what continuing education is for? If the people on this thread understand all this stuff, she sure should have been able to as well. I hate relying on Google as a research tool, but when I can't trust what I'm hearing from the NP, what other choice do I have? My Mayo Clinic Guide to a Healthy Pregnancy doesn't go into THIS much detail!

And rowan, I love this:
Yes, absolutely! It's one thing to be realistic about chances, it's another to scare the fuck out of people.


not excited about others' pregnancies

Fri Jan 22 8:53 PM by lyra211 in Pregnancy & Parenting

This thread makes me want to make a graph of my excitement levels about other people's pregnancies. It would start off quite mild through teenage years and college, start to spike in early adulthood when I started thinking about maybe being pregnant someday but it was still a distant future possibility, reach a high right around the time my first friends started getting pregnant, drop a little when my husband and I started trying and encountered issues (took us 11 months first time around with my irregular cycles), reach a frenzied crescendo around the time I got pregnant (I was super-excited about being pregnant at the same time as one of my best friends -- we were due with baby girls within a week of each other). Then it dropped like a rock to the depths of deepest despair when our first daughter died at 18w2d in my first pregnancy -- I just couldn't bear to see other pregnant women, especially smug pregnant women who were rubbing their bellies all the time and had the nursery painted by the middle of the second trimester. Now that I'm 36 weeks pregnant with our second, a son, my excitement levels about other people's pregnancies are generally about where they were in teenage/college years, although now tinged with a huge amount of cynicism. Since everyone I know is pregnant at my age, I couldn't care less if someone I know is due within a few weeks of me -- I've been there before. Someone pregnant for the first time and over the moon? I remember feeling that way. It didn't end well. I'm >8 months pregnant, and I still get intensely jealous of first-time pregnant women who have never experienced problems. Heck, I still feel stabs of jealousy when I see other pregnant women rubbing their bellies. I've spent my whole pregnancy mentally keeping my kid at arms' length, not really believing that he's going to be born. I'm still emotional and excited about my pregnancy, but it's all dulled considerably compared to what I felt the first time around -- and I spend much more time worrying and educating myself about potential problems.


Toys that make noises

Wed Jan 6 8:44 PM by melsbells in Pregnancy & Parenting

I definitely don't like these types of toys. I was so grateful when my brother asked how we felt about electronic toys before purchasing one for our kid. Unfortunately, most people don't ask, and even if they know don't care. Our general policy is to not replace batteries when they die, but we haven't caused any to die myteriously. The only batteries we have in the house are attached to a phone, a laptop, and a couple spares for a flashlight.

Just today I heard about this small study on the effects of electronic toys, which didn't really surprise me.

Results Among the 26 parent-infant dyads, toy type was associated with all outcome measures. During play with electronic toys, there were fewer adult words (mean, 39.62; 95% CI, 33.36-45.65), fewer conversational turns (mean, 1.64; 95% CI, 1.12-2.19), fewer parental responses (mean, 1.31; 95% CI, 0.87-1.77), and fewer productions of content-specific words (mean, 1.89; 95% CI, 1.49-2.35) than during play with traditional toys or books.


holiday shopping lists - kids/babies edition!

Mon Dec 14 8:49 PM by ladyhawk in Pregnancy & Parenting

We had something similar happen on the oldest's birthday last year. We had a talk with him about how he was fortunate, and had a lot of things, and asked him to consider sharing with less fortunate kids. He ended up leaving half of them unopened and we took them to the children's hospital.


Childbirth/infant cpr/baby care classes

Mon Nov 2 11:25 PM by antfancier in Pregnancy & Parenting

Thanks everyone! Lots for me to think about...

I have just started prenatal yoga and it seems that it will be pretty useful - although it's way more physical hard work than I expected (I'd better get used to it now, I guess).

Also, I hope I get an inflatable baby from whichever course I end up going with.


Group B Strep

Wed Feb 3 2:02 AM by lyra211 in Pregnancy & Parenting

It's not at my (US) hospital, alas, and I got the impression it is not common. :-( I am just planning to eat a bunch of yogurt and other probiotic stuff after birth and hope for the best (there's apparently some evidence that good bacteria can be passed through breast milk, so hopefully as I rebuild my own microbiome I'll also be helping my baby to build his). I'm simply not willing to take the risks associate with passing up antibiotics, so I think focusing on rebuilding a healthy microbiome is probably the best I can do.


'Forest' preschools

Mon Jan 11 3:21 AM by rowan in Pregnancy & Parenting

It's currently -22 C here and didn't get above -18. The wind was pretty bad too, which makes it worse. *shrug* Brisk activity would have been fine, like sledding or skiing, if it hadn't been for the wind, but trying to actually learn things I think would be much more challenging. Not the least of which is it would damage any equipment you were trying to use. I don't think you could really sustainably do it for the entire winter, or at least not for January and February.


speaker tampon lets you play music to your fetus

Tue Jan 5 5:36 PM by Aum in Pregnancy & Parenting

^ You'd have to pick something like heavy metal or drum & bass. Your kid would turn out all punk as a result, so it's win-win!


disapproving babies

Mon Dec 7 3:04 AM by Bork in Pregnancy & Parenting

I think your baby totally wins the "disapproving baby" contest. Her face is amazing. She's got the eyebrows and the mouth and oh man.


Postpartum girdle?

Fri Oct 23 2:47 PM by rowan in Pregnancy & Parenting

Interesting to hear everyone's stories about recovery. I still have issues with some of my ab muscles, I wonder if it would have helped.