Natural family planning provides no protection from STIs and restricts spontaneity. In addition, this method has low effectiveness rates, takes time and commitment to learn, and requires several cycles of records before it can be used reliably. In addition, women who have irregular cycles may have difficulty in interpreting their charts.

Cross-Cultural Use

What makes natural family planning so popular in many areas outside the United States is the fact that it is inexpensive and involves little assistance from physicians. Natural family planning may also be the only form of acceptable contraception in Catholic countries such as Ireland, Brazil, and the Philippines. In the Philippines nat­ural family planning and the rhythm method are thought to improve a couple’s rela­tionship because they need to work together to use the method (Leyson, 2004). Societal issues and marketing may also affect the use of this method. For example, cul­tural resistance to condom use has increased the popularity of natural family planning
in Kenya, where it is the most commonly used contraceptive method (Brockman, 2004). Today, many women’s groups from the United States travel to developing coun­tries to teach natural family planning.