The theory: Ob-gyns joke that more babies make an entrance when the moon is full—and in some ancient cultures, the moon was a fertility symbol. (Come to think of it, it does kinda resemble a pregnant belly.)
The truth: Chalk this one up to superstition, say scientists. Studies of births haven’t found an uptick when the night sky is well lit. Doctors still aren’t quite sure what brings on labor (aside from: not the moon). One hypothesis is that once a fetus’s lungs are mature, its body releases a protein that initiates contractions.
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