Avoiding Pregnancy using the Sympto-thermal Method of NFP

What’s it all about?

The Sympto-thermal method is a natural method of family planning based on the observation of the signs and symptoms of the fertile and infertile phases of the menstrual cycle.  Awareness of the fertile phase allows a couple to time intercourse to avoid a pregnancy.

The Sympto-thermal method uses self-observation of the cervical mucus and the basal body temperature to define the fertile phase of the cycle.  A double-check is used at the beginning of the fertile phase (mucus observation and/or calendar calculation) and also at the end of the fertile phase (temperature rise and mucus observation).

The Sympto-thermal method of natural family planning, when used correctly is 99.6% effective in avoiding a pregnancy.


Can anyone use it?

Sympto-thermal method can be used by women whether they have long, average or short cycles, are breastfeeding, discontinuing contraception or are peri-menopausal.

The couple need to be taught how to identify the difference between basic infertile type mucus and fertile type mucus as well as changes in their temperature.

Any couple, who has been taught how to recognise and interpret their signs and symptoms of fertility, can manage their family planning needs naturally without recourse to contraceptives.


Usefulness of Mucus

The ability to detect and interpret the mucus symptom is beneficial to women who are trying to achieve a pregnancy as well as those wishing to avoid pregnancy.


After ovulation occurs, progesterone levels rise causing the mucus to thicken and causing the body temperature to change.  See Sympto-thermal Natural Family Planning for more information. (link to this page)


ADVANTAGES of the Sympto-Thermal Method of NFP

The Sympto-thermal method is a multi-indicator approach to fertility management.  The variety of indicators used in the decision making process offer reassurance to the couple when one indicator is less obvious than usual.  The advantages are as follows:

  • The fertile and infertile phases of the cycle can be determined.
  • Husbands can assist in charting procedures and share in decision-making.
  • Fertility information is available for medical assessment in times of infertility investigation or unusual pathology.
  • Knowledge of all the indicators gives couples the freedom to chart all the signs or to adopt the combination of indicators that suit them best.

Separate indicators can be of value during particular stages of reproductive life, especially during breastfeeding and the shift into peri-menopause.


Through daily charting women become familiar with their own unique fertility signs.

DO YOU KNOW That a woman’s body is a walking biological computer revealing the most enlightening information about her fertility?  All women can learn how to observe and chart the fertility signs that their bodies produce each menstrual cycle.  This information helps women become aware of their own fertility status and whether they can or cannot get pregnant on any given day of their cycle.


Want to know more please call your Natural Fertility Educator for an appointment now to begin the journey.



WHO taskforce (1983): a prospective multicenter trial of the Ovulation Method of Natural Family Planning III Characteristics of the menstrual cycle and of the fertile phase, Fertility and Sterility. 40, p. 773


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