Typical, 28-Day Cycle

In a typical, 28-day cycle, the selection of the dominant follicle occurs approximately 5-7 days before ovulation.  By tracking the changes in the concentration of electrolytes in your saliva, the OvaCue® Fertility Monitor is able to detect the hormonal changes that coincide with the selection of the dominant follicle.  When the dominant follicle is selected, the OvaCue® will identify a Cue Peak in your oral readings, and can then predict out your fertile window for 5-7 days in the future.  The Cue Peak is defined as a high oral reading followed by two lower oral readings.  In the graph below, the Cue Peak occurs on Cycle Day 9.    

With the vaginal sensor, the OvaCue® tracks changes in the electrolyte levels in the cervical mucus, which allows the monitor to detect the switch from estrogen to progesterone dominance that accompanies ovulation.  As you interpret your vaginal readings, it is important to remember that low vaginal readings indicate high levels of estrogen and/or low levels of progesterone and high vaginal readings indicate low levels of estrogen and/or high levels of progesterone. 

For women with typical hormone levels and trends, the vaginal readings will trend downward following the Cue Peak, reflecting the high estrogen levels that are present immediately before ovulation.  Remember that you are most fertile when your vaginal readings are low.  When ovulation occurs, your vaginal readings will rise sharply (called the Vaginal Rise), signaling the switch in your body from estrogen to progesterone dominance.  In the graph below, the Vaginal Rise occurs on Cycle Day 15 and ovulation is confirmed.

Under normal circumstances, the vaginal readings will remain elevated following ovulation until the end of the luteal phase of the cycle.  This indicates that progesterone levels are remaining high, which is necessary for successful implantation of the embryo if conception occurs.  As you can see in the graph below, the vaginal readings remain elevated through Cycle Day 28.