During a woman’s menstrual cycle, there are only about three days when her egg is available for fertilization. Sperm can survive up to 72 hours (3 days) in the vagina and uterus, so if sexual intercourse occurs up to three days before a woman is fertile, she can still potentially become pregnant. Thus, there are about six days per month (3 days prior to fertility, and 3 days of fertility) that a woman can conceive.
When tracking the days of the menstrual cycle, the first day of menstruation, or bleeding, is called day 1 of that cycle. The cycle ends when the next period begins, anywhere between day 17 and 35 (with most women it’s around day 28). The egg may become available for fertilization by sperm at anywhere from day 3 to day 14 of the cycle. Thus, if a woman can identify those few days when she is fertile, she can prevent or enhance conception.
As mentioned in The History Of Saliva Ferning, saliva has been used to detect patterns in the body for years. Now with this information and the power of understanding the hormonal cycles and patterns of woman, we can use this to our advantage. One does not have to be a scientist to match up a few simple patterns viewed through the eyepiece.
When a women is in an infertile time and estrogen is low typically she would see a random pattern of scattered dots. This marks these days as infertile. This is of course the safest time if one does not wish to conceive and would account for somewhere about 22-24 total days, before and after ovulation of course, in a “normal” 28 day cycle.