Basal body temperature (BBT) is the body’s temperature at rest. It can be measured in the mouth, rectum, or vagina, ideally right after waking up while still lying in bed. When measured correctly and consistently, changes in BBT can help identify when ovulation has happened or which cycle phase a person is in.
Wearable devices measure your temperature from the skin of your finger or wrist; therefore, this reading is not the same as BBT. Nonetheless, skin temperature can also be an insightful tool for understanding changes in your body, because increases in BBT almost always coincide with increases in skin temperature.
If you’re not using hormonal birth control, measuring temperature with your wearable and syncing it with Clue can provide further insights into your personal patterns across different cycle phases. Read more about the benefits here.