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Birth rate and its correlation with the lunar cycle and specific atmospheric conditions
Susan Morton-Pradhan1, R Curtis Bay, Dean V Coonrod
1Department of Obsetetrics, Gynecology and Women's Health, Maricopa Integrated Health System/MedPro, Phoenix, AZ, USA.
Objective:
This study was undertaken to use the Arizona State birth certificate database for Phoenix metropolitan hospitals, in conjunction with National Weather Service records to determine whether there is a relationship between birth rate and meteorologic or lunar conditions. This study attempts to dispel or lend significance to beliefs among hospital staff that the phase of the moon and/or meteorologic conditions are related to birth rate.
Study Design:
Birth records were limited to spontaneous vaginal deliveries, 37 to 40 weeks' gestation, in Phoenix, between 1995 and 2000 (n = 167,956). Daily birth counts were merged with daily surface weather statistics from the National Weather Service for Sky Harbor Airport, and records of lunar phase for the same period.
Results:
The analyses revealed no significant correlates of birth rate.
Conclusion:
Although there exists a popular belief that the phase of the lunar cycle and weather conditions affect birth rate, no such evidence was found in this study.
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