Female Body Temperature -- Daily & Menstrual Rhythms
by Mike Martin

This page presents a model of two processes known to impact the body temperature of females over the course of a day and over the course of a 28-day menstrual cycle.   The daily cycle can be written as

The average body temperature is Tave, the variation in the daily temperature is ΔTday, and the peak temperature occurs at tday. Note that this formula gives the temperature as a function of time in hours.   The monthly cycle can be written as

The average body temperature is again Tave, the variation in the monthly temperature is ΔTmonth, and the peak temperature occurs at tmonth. Note that this formula gives the temperature as a function of time in days.   When the two temperature cycles are combined the formula becomes

Note that this formula gives the temperature as a function of time in days. The default values are consistent with observations -- the variations, the average temperature, the maximum daily temperature occurs at about 14 hours, and the maximum temperature over a 28-day cycle (that begins with menstruation) occurs at about the 16th day. While the parameter values are typical for assumed sinusoidal models, the user can vary the parameters to investigate the combination of these two sinusoids.

Enter in the values of the parameters, then press the "Visualize" button.

Tave   =   °F

ΔTday   = °F

ΔTmonth = °F


tday   =   hours

tmonth = days