Seasonal Behavior of Human Menstrual Cycles: A Biometric Investigation

Document Type

Article

Authors

N Sundararaj, University of Agricultural Sciences, Bangalore, India
M Chern, University of Minnesota, Minneapolis, Minnesota
L Gatewood, University of Minnesota, Minneapolis, Minnesota
L Hickman, Logical Machine Corporation, Sunnyvale, California
R McHugh, University of Minnesota, Minneapolis, Minnesota

Abstract

Menstrual histories representing 38,194 woman-years were analyzed for seasonal periodicities using a simple additive model incorporating a secular trend. A recurrent sinusoidal pattern for cycle length was found which varied by 0.08 days throughout the year, decreasing during the warmer days of spring and summer, and increasing in the fall. Separate analyses of cycle variability and numbers of cycles indicated similar results but without as clear an effect. Although these variations were statistically different from random deviations occurring during the year, they were not large enough to indicate any physiological relationship

Recommended Citation

Sundararaj, N; Chern, M; Gatewood, L; Hickman, L; and McHugh, R (1978) "Seasonal Behavior of Human Menstrual Cycles: A Biometric Investigation," Human Biology: Vol. 50: Iss. 1, Article 4.
Available at: https://digitalcommons.wayne.edu/humbiol/vol50/iss1/4