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:
“The ancient bitter opposition to improved methods [of production] on the ancient theory that it more than temporarily deprives men of employment ... has no place in the gospel of American progress.”
—Herbert Hoover (1874–1964)
“If men got pregnant, there would be safe, reliable methods of birth control. They’d be inexpensive, too.”
—Anna Quindlen (b. 1952)
“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 (1817–1862)