No. Couples with little or no formal schooling can and do use fertility awareness methods effectively. Couples must be highly motivated, well-trained in their method, and committed to avoiding unprotected sex during the fertile time.
For many couples, these methods provide reliable information about the fertile days. If the couple avoids vaginal sex, or uses condoms or a diaphragm during the woman’s fertile time, fertility awareness methods can be effective. Using withdrawal or spermicides during the fertile time is less effective.
These fertility awareness methods are easier to use correctly than some of the older ones. Thus, they could appeal to more couples and be more effective for some people. They are like older methods, however, in that they rely on the same ways of judging when a woman might be fertile—by keeping track of the days of the cycle for the Standard Days Method and by cervical secretions for the TwoDay Method. So far, there are few studies of these methods. A clinical trial found that, as the Standard Days Method was commonly used by women who had most cycles between 26 and 32 days long, there were 12 pregnancies per 100 women over the first year of use. In a clinical trial of the TwoDay Method as it was commonly used, there were 14 pregnancies per 100 women over the first year of use. This rate is based on those who remained in the study. Women who detected secretions on fewer than 5 days or more than 14 days in each cycle were excluded.
During monthly bleeding the chances of pregnancy are low but not zero. Bleeding itself does not prevent pregnancy, and it does not promote pregnancy, either. In the first several days of monthly bleeding, the chances of pregnancy are lowest. For example, on day 2 of the cycle (counting from the first day of bleeding as day 1), the chance of getting pregnant is extremely low (less than 1%). As the days pass, the chances of pregnancy increase, whether or not she is still bleeding. The risk of pregnancy rises until ovulation. The day after ovulation the chances of pregnancy begin to drop steadily. Some fertility awareness methods that depend on cervical secretions advise avoiding unprotected sex during monthly bleeding because cervical secretions cannot be detected during bleeding and there is a small risk of ovulation at this time.
The number of days varies based on the woman’s cycle length. The average number of days a woman would be considered fertile—and would need to abstain or use another method—with each method is: Standard Days Method, 12 days; TwoDay Method, 13 days; symptothermal method, 17 days; ovulation method, 18 days.