How to Interpret Basal Temperature Charts
- 1). Locate your baseline basal temperature reading. Most basal temperature charts show between 12 and 14 days of temperature readings below the 98 degree Fahrenheit mark at the beginning of the cycle. The first day of readings should be the first day of your period. The highest of these readings is your baseline temperature. Draw a horizontal line through this plot point from one end of the graph to the other to clearly mark this reading.
- 2). Identify your ovulation period. Three consecutive days of temperatures above the baseline indicate when ovulation occurred.
- 3). Identify your period of heightened fertility. The two to three days before ovulation and the 12 to 24 hours after ovulation are considered your most fertile days.
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