Natural Family Planning
What is the symptothermal method?
The symptothermal method is a means of natural family planning that involves abstaining from sexual intercourse on days that a women is fertile, or capable of getting pregnant.
How does the symptothermal method work?
To use the symptothermal method, a woman needs to learn about her body's natural fertility signs and also take her temperature every morning. Daily temperature readings are performed using a basal thermometer, a special thermometer that will determine the body's temperature within a few hundredths of a degree. This level of precision is necessary to detect the slight temperature increase that marks the end of the fertile period. The woman keeps a chart where she records her daily temperature and also other body signs that indicate when ovulation will occur. Other body signs include cervical mucus consistency, cervical position, mid-cycle cramping, and mood. To use this method, couples should receive training from a certified natural family planning instructor.
How effective is the the symptothermal method?
Annual Failure Rate
Among experienced users, the symptothermal method has an overall annual failure rate of 13-20%. That means each year about 1 in 7 users of this method experience a surprise pregnancy. For perfect users, the method has a failure rate of only 2-3%, but this method is completely ineffective if used incorrectly. For women who feel uncomfortable touching their bodies, this method can be used without recording information about cervical position or cervical mucus, but this will make the method less effective. Such women should consider the standard days method instead.
Side-effects and health risks of the the symptothermal method
Like other methods of natural family planning, there are no side effects or health risks because the user does not put anything into her body. There are no hormones, chemicals, or surgical procedures involved.
Considerations for Christians about the symptothermal method
Most Christians do not have a moral objection to this method of natural birth control. This method is also acceptable to the Roman Catholic Church.
- Christian Family Planning Network: Provides education for Christian couples about natural birth control (ChristianFamilyPlanning.net)
- Sympto-Thermal Methods: Contraceptive Information Resource (Contracept.org)
- The New Two Day Method of Natural Birth Control: Contraceptive Information Resource (Contracept.org)
- Natural Family Planning: Epigee Women's Resources (Epigee.org)
Source for Failure Rates: D Kowal, "Fertility Awareness-Based Methods," In Hatcher et al, Contraceptive Technology, Ardent Media, 2004.