It has a dual purpose:

• For those who wish to conceive allows to determine the most probable days in which the woman is fecundable and, within these, the days where the probability of fertilization is maximum, and therefore more favorable to conception.

• For those who do not want to conceive allows to determine the days when the woman is not fecundable.

The Ogino-Knaus method must be combined with other contraceptive methods for a greater likelihood of success.

It is very important to correctly calculate the infertile days, because the errors of calculation of the infertile days are the main causes of the failure of the Ogino-Knaus method, creating a new group of human beings: Ogino Knaus's children.

The purpose of this application is to calculate the fruitful and infertile days of the menstrual cycle in a precise, simple and rapid manner. Moreover the app allows to calculate the duration, expressed in number of days, of the menstrual cycle knowing the dates of two successive cycles.

Attached to the application there is the documentation on the Ogino-Knaus method, and before applying the method it is advisable to read it carefully, also to realize on what the digital calculation of the fertile and infertile days is based.