How effective is the Fertility Monitor?
There are three risk levels in the Fertility Monitor. This feature allows you to choose between rules which are strict and others which are more relaxed. The more relaxed rules allow more days for coitus with a corresponding increase in the chance for pregnancy. If you choose the lowest possible risk you would become pregnant only once in over a hundred years of use at this level. If you choose the highest risk you would become pregnant 3 to 7 times in one hundred years of use according to estimates by natural family planning experts.
