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
0	35
1	125
2	118
3	104
4	117
5	115
6	116
7	101
8	142
9	114
10	115
11	95
12	102
13	106
14	108
15	109
16	125
17	100
18	103
19	108
20	119
21	102
22	120
23	113
24	104
25	90
26	108
27	118
28	106
29	110
30	6

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

Days away from the new moon	# of babies spontaneously born
0	35
1	125
2	118
3	104
4	117
5	115
6	116
7	101
8	142
9	114
10	115
11	95
12	102
13	106
14	108
15	109
16	125
17	100
18	103
19	108
20	119
21	102
22	120
23	113
24	104
25	90
26	108
27	118
28	106
29	110
30	6

Days away from the new moon	# of babies spontaneously born
0	35
1	125
2	118
3	104
4	117
5	115
6	116
7	101
8	142
9	114
10	115
11	95
12	102
13	106
14	108
15	109
16	125
17	100
18	103
19	108
20	119
21	102
22	120
23	113
24	104
25	90
26	108
27	118
28	106
29	110
30	6

Days away from the new moon	# of babies spontaneously born
0	35
1	125
2	118
3	104
4	117
5	115
6	116
7	101
8	142
9	114
10	115
11	95
12	102
13	106
14	108
15	109
16	125
17	100
18	103
19	108
20	119
21	102
22	120
23	113
24	104
25	90
26	108
27	118
28	106
29	110
30	6