Helping You Monitor Your Fertility

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"Saliva ferning should not be used as the sole method of fertility prediction. It should only be charted alongside other fertility symptoms. It is not always a good indicator of fertility by itself."


Ovulation Calendar


Saliva ferning is a newer symptom that can be included on charts. Fertility awareness traditionally charts basal body temperature and cervical mucus observations with an optional area to also record cervix state. Saliva ferning is an additional optional symptom like cervix state. It should not be charted by itself though since its correlation with ovulation is not as well established as the primary three symptoms mentioned. Saliva ferning is not conclusively supported by clinical research.

Saliva Ferning

Saliva ferning is a technique that monitors female saliva and looks for patterns related to ovulation and fertility. Saliva is inspected under a handheld microscope for crystallization patterns. The microscopes usually offer 60 to 100 times magnification. These crystal patterns look like ferns. During infertile parts of your cycle, the saliva should not exhibit any crystallization or ferning patterns. As fertility increases, the ferning patterns should begin to develop and become more significant.

Saliva Ferning Patterns

An example of saliva ferning patterns is shown. The term ferning is used due to the similarity of the patterns to a fern plant. During infertile parts of the cycles, no ferning patterns are present. Only dots and simple lines will be present. A transitional pattern begins as ovulation nears. Small fern-like crystals start to appear in isolated areas. Immediately before and during ovulation, more intense ferning patterns will be apparent.

The hormone estrogen links saliva patterns to your fertility. As ovulation nears, estrogen increases and causes the body's sodium levels to rise. Saliva is affected by the increased salinity. This is noticeable when allowing samples of saliva to dry. Near ovulation the higher salt content causes the dried saliva to form crystallization patterns. Both saliva and cervical mucus have shown these patterns.


  1. This technique requires a special handheld saliva microscope.
  2. Consider taking a sample first thing in the morning before eating, drinking, or brushing your teeth. If taken later, you should ensure that you have not eaten or drunken anything for at least two to three hours
  3. Take a sample of saliva from under your tongue
  4. Smear the saliva sample on the microscope slide. Try to avoid the formation of bubbles.
  5. Wait about five minutes for the saliva to dry
  6. View the saliva based upon directions included with your handheld microscope. Record the observed results on your fertility chart.

Recording on Charts

Saliva ferning patterns are classified into 3 different types which are recorded. A separate letter is put on the chart to indicate each value similar to cervical mucus. These letters are typically as follows:

  • N - Used to indicate N ferning. This indicates low fertility levels.
  • T - Used to indicate Transitional ferning. This is somewhere in between full ferning patterns and no ferning patterns. This suggests that ovulation is nearing and your chances of getting pregnant are on the rise.
  • F
  • - Used to indicate the presence of Ferning patterns. This occurs right around ovulation when fertility is highest.
The presence of ferning patterns indicates the vicinity of ovulation and high fertility. A specific pattern between ferning and ovulation is difficult to capture. It has been suggested that ovulation occurs 72 hours after the first ferning pattern well beyond menstruation. This does not appear to be universal in all women though, but can be used as an estimate.


  • Can offer another data point to compare against other charted symptoms.
  • Saliva samples can be easily taken and analyzed.


  • Requires practice to understand the variation in ferning patterns.
  • Does not always pinpoint ovulation as precisely as other commonly charted symptoms!
  • Scientific studies have found saliva ferning much less effective than other techniques
    • Several studies have failed to find a strong relationship between ferning and ovulation.
    • Even in favorable studies where ferning tends to correlate to ovulation, it still does not work for all participants in the study.
    • The ferning pattern varies widely in how early and late in the cycle it is seen. This reduces its usefulness for many.
    • Some woman may not experience saliva ferning patterns at all.
  • Because of its shortcomings, this technique should only be charted for consideration alongside other charted symptoms.