The Fertility Tracker® Saliva Fertility Monitor uses your saliva each day to determine your personal fertility status. It monitors levels of estrogen known to rise in the pre-ovulation part of the cycle. There are about 6 days in which you can conceive and the rise of estrogen and subsequent saliva ferning that occurs will help you pin point when you are ovulating. The Fertility Tracker® is the easiest, most affordable way to get the best possible results using saliva ferning methods. Many other pocketsize microscopes offer simple results but The Fertility Tracker® has the advantage over them all with it's powerful 100X illuminated magnification. This allows one to notice changes in saliva or cervical patterns earlier than the smaller microscopes. BUT The Fertility Tracker® also has the convenience of small size yet is sturdy. Where a pocket microscope has one slide surface the The Fertility Tracker® comes with a 6 slides allowing women to re-view their previous days results. This product is ideal for people with longer or irregular cycles. Friendly and Helpful support is offered by company owner, after you buy for useage issues and other infertility related issues.