Methods
There are three main types of NFP: the symptoms-based methods, the calendar-based methods, and the breastfeeding or lactational amenorrhea method. Symptoms-based methods rely on biological signs of fertility, while calendar-based methods estimate the likelihood of fertility based on the length of past menstrual cycles.
Clinical studies by the Guttmacher Institute found that periodic abstinence resulted in a 25.3 percent failure under typical conditions, though it did not differentiate between symptom-based and calendar-based methods.
Read more about this topic: Natural Family Planning
Famous quotes containing the word methods:
“It would be some advantage to live a primitive and frontier life, though in the midst of an outward civilization, if only to learn what are the gross necessaries of life and what methods have been taken to obtain them.”
—Henry David Thoreau (18171862)
“If you want to know the taste of a pear, you must change the pear by eating it yourself.... If you want to know the theory and methods of revolution, you must take part in revolution. All genuine knowledge originates in direct experience.”
—Mao Zedong (18931976)
“Commerce is unexpectedly confident and serene, alert, adventurous, and unwearied. It is very natural in its methods withal, far more so than many fantastic enterprises and sentimental experiments, and hence its singular success.”
—Henry David Thoreau (18171862)