[Births, fertility, rhythms and lunar cycle. A statistical study of 5,927,978 births].

Is there any relationship between the times when babies are born and the synodic lunar cycle? There are published works that show that there is such a relationship. We have looked at 5,927,978 French births occurring between the months of January 1968 and the 31st December 1974. Using Fourier's spectral analysis we have been able to show that there are two different rhythms in birth frequencies: --a weekly rhythm characterised by the lowest number of births on a Sunday and the largest number on a Tuesday: --an annual rhythm with the maximum number of births in May and the minimum in September-October. A statistical analysis of the distribution of births in the lunar month shows that more are born between the last quarter and the new moon, and fewer are born in the first quarter of the moon. The differences between the distribution observed during the lunar month and the theoretical distribution are statistically significant.