The OvaCue and the Cue II uses Zetek's patented electrolyte method for measuring changes in the body associated with ovulation using vaginal and oral sensors.

The OvaCue is a significant advance in that it does the calculations for predicting and confirming ovulation itself and reports a visual indicator of your fertility status for the day and a projected date of peak fertility. OvaCue also tracks and stores information about your cycles for up to 4 months automatically in its internal memory chip.  When purchasing a complete kit, we include the OvaGraph software absolutely FREE.

You record daily readings and interpret the pattern according to instructions.  Combining the vaginal sensor with either device allows you to completely define the fertile window.

A few days after the Cue Peak, the luteinizing hormone (LH) in the blood increases and decreases very sharply over a period of 24 hours (the LH surge). As LH reaches its peak in the blood, there is a definite change in the reproductive tract which can be measured by the Cue vaginal sensor. Mucus secretion increases, and the electrolyte content of the mucus changes. This change causes a sharp, clear drop and increase in these readings. It is this nadir and subsequent rise that the Cue uses to confirm ovulation.  Read more on our OvaCue page.