Definition - What does Symptothermal Method (STM) mean?
Symptothermal method (STM) is a fertility awareness-based method of family planning that uses a woman's observations of her physiological signs of fertility to determine the fertile and infertile phases of her menstrual cycle.
The "sympto" in symptothermal refers to symptoms, specifically changes in cervical mucus, and the "thermal" refers to basal body temperature (BBT). STM may be used to avoid or to plan a pregnancy.
An egg is only viable for 24 hours after ovulation. However, sperm can survive in the right conditions for up to 5 days. This means the maximum number of fertile days for a woman is 6 days of each month. STM helps women identify these days and make decisions on abstinence, use barrier methods, or to time sex to achieve pregnancy, depending on the outcome desired.
Basal body temperature (BBT) is a daily reading of temperature taking first thing in the morning, prior to any activity. Tracking BBT with a basal body thermometer is an effective tool for determining when ovulation will occur.
Cervical mucus (CM) plays an important role in sperm survival and transport. CM with an egg white-like consistency is referred to as peak CM and provides optimal conditions for sperm survival. Understanding when CM is most fertile is important to determine an overall fertile window.
Tracking these two physiological signs together can provide a clear understanding of the maximum 6 days per month (5 days prior to ovulation, the day of ovulation) that a woman is fertile.
Additional signs including cervical position and secondary signs including sex drive, mood, and breast tenderness may also be observed.
When the appropriate guidelines are consistently adhered to, STM is considered to be a highly effective method of family planning. Learning to practice the STM accurately requires education. This may be in the form of a book like Taking Charge of Your Fertility or through the guidance of a fertility awareness educator.
While the STM is a method of fertility awareness, it differs from other family planning methods like the rhythm method or calendar method that attempt to calculate a fertile window based on previous cycles. STM is not predictive but rather focuses on current physiological signs of fertility to determine when a fertile window is.