What is going on with this chart?
1) Low temperatures persist from days 1-39 of this woman's cycle, indicating that ovulation has not occurred.
2) Even though this woman observes eggwhite cervical fluid on days 19-21 of her cycle, her temperatures remain low, indicating that she experienced a 'false peak', in which cervical fluid becomes more fertile, but ovulation does not occur.
3) She observes eggwhite cervical fluid again on days 38-39.
4) This time, she observes a sustained temperature shift following the observation of eggwhite cervical fluid, indicating that ovulation occurred. Her temperatures remain high for the rest of her cycle.