In part 1, we discussed using a test kit to determine fertility, and in part 2, we covered how cervical fluid changes predict ovulation. In this, the final installment, we talk about basal body temperature and its relation to fertility.
After you ovulate, your body temperature will rise and stay at a higher-than-normal level for the rest of your ovulation cycle. At the end of your cycle, it falls again. You can take your temperature in the morning before you get out of bed.
Use a glass basal thermometer or a digital thermometer so that you can get accuracy to the tenth of a degree. Keep the thermometer in your mouth for 5 minutes or until it signals that it is done. Try not to move too much, as activity can raise your body temperature slightly.
If your temperature is between two marks, record the lower number. Try to take your temperature at the same time every day, if possible. Create a chart and write down your temperature every day. If you look at a complete cycle, you will probably notice a point at which the temperature increases 0.2 degrees or more above the previous 6 days.
After monitoring several cycles, you may be able to see a predictable pattern and identify your most fertile days.