Basal body temperature
Tracking Basal Body Temperature for Fertility Charting - FertilityTips.com
When you are trying to conceive, you naturally want to increase the odds that you will become pregnant. One of the best ways to do that is to chart your fertility cycles. It lets you know when exactly is the best time to try to conceive. Tracking your basal body temperature (BBT) is a good place to start.