Fertility Education Trust

understanding your fertility, page 11 of 14

Charting the Fertility Cycle

Cycles can be explained and charted in many different ways. This colour scheme, based on the seasons of the year as seen in trees, helps to highlight the fertile and non-fertile phases of the cycle. Red represents the period.

The fertility cycle represented by the seasons of a tree: winter - summer winter.

Brown (the bare winter tree) represents the “winter” time of the cycle - the infertile time when the “mesh” mucus plug is present, blocking the access of sperm.

Green (the green summer tree) represents the “summer” time of the cycle - the fertile time, when the egg is ripening and the “motorway” mucus is being secreted.

Below are three cycle patterns displayed with this colour scheme.

A short cycle is typically between 22 and 24 days.

Fertile mucus (green block) starts straight after the period, possibly even before the period has actually stopped. The mucus continues for about 5 - 6 days and the last day of it is called PEAK Day (peak of fertility) - marked P on the chart. Ovulation occurs around PEAK Day. After a count of 3 dry days (brown block 1,2,3) to allow for the release and lifespan of the egg, the remaining brown days are infertile till the next period starts.

An average cycle is typically between 27 and 31 days.

A few DRY infertile days (brown block) usually follow the period. Then the fertile mucus appears (green block) and leads up to ovulation around PEAK Day. After the count of 3 dry days after Peak, the rest of the cycle is infertile (brown block) until the next period starts.

A long cycle is typically 5 to 6 weeks, but can be longer.

The DRY infertile days after the period (brown block) stretch to several days (even weeks, in really long cycles). Eventually the fertile mucus appears (green block), leading up to ovulation around PEAK Day. After the count of 3 dry days after PEAK, to allow for the release and life span of the egg, the rest of the cycle is infertile (brown block).

For those trying to achieve pregnancy, the PEAK Day (the last day of the fertile mucus i.e. last day of green block) is the most fertile day of the cycle!

the above charts are not intended to be used alone. please see subsequent pages to learn how to double check symptoms using the temperature and other indicators.