Symptothermalmenetelmä

The symptothermal method is a natural family planning technique used to identify a woman's fertile and infertile phases of the menstrual cycle. It combines two primary fertility indicators: basal body temperature (BBT) and cervical mucus observations. By tracking these signs daily, a woman can pinpoint ovulation and predict her fertile window.

Basal body temperature is measured first thing in the morning before any activity, upon waking. A slight, sustained rise in temperature, typically 0.2 to 0.5 degrees Celsius, occurs after ovulation due to increased progesterone. Cervical mucus changes throughout the cycle. Before ovulation, mucus becomes clearer, more slippery, and stretchy, resembling raw egg white, indicating high fertility. After ovulation, it becomes thicker, cloudier, and less abundant, signaling infertile days.

When used consistently and correctly, the symptothermal method can be highly effective in achieving or avoiding pregnancy. It requires diligent daily recording of temperature and cervical mucus changes, often using a fertility chart or app. Couples using this method need to abstain from intercourse or use a barrier method during the identified fertile window if they wish to avoid pregnancy. Conversely, if conception is desired, intercourse can be timed during this fertile period. The effectiveness of the method relies on accurate observation and interpretation of the fertility signs.