I understand that my temperatures will fluctuate slightly from day to day, but mine seem to be all over the place! Is that normal?
Temperatures will generally go up and down from day to day by about 0.1 to 0.2 ℃. Erratic temperatures that fluctuate by 0.3 ℃ or more may be due to a number of reasons.
Firstly, don’t worry if this is happening during your period. It’s quite common for temperatures to be high or erratic during this time. They should settle within a few days.
Make sure that you are taking your temperatures consistently each day, at approximately the same time and after at least a 3-hour block of sleep. Ensure also that you have a good quality thermometer and that the batteries don’t need changing. Some thermometers beep slowly while recording your temperature and then emit a number of fast beeps on completion. So if you have one of these, make sure you don’t whip the thermometer out of your mouth on the first beep!
Remember also, that factors such as unsettled sleep, illness or alcohol the night before can cause significant changes in temperature.
If none of these factors are contributing to your erratic temperatures, you may want to consider taking your temperature vaginally (ie carefully place the thermometer inside your vagina each morning, instead of in your mouth). Whichever way you decide to take your temperature (orally or vaginally), just make sure that you continue to use the same method throughout your cycle.