Basal temperature is the normal body temperature of a healthy person immediately upon awakening in the morning. During ovulation, hormonal changes occur which produce a slight rise in a woman's basal body temperature as well as other signs such as changes in cervical mucus. By monitoring the basal temperature changes and consulting their physician or family planning counselor, couples may be able to determine if, and approximately when, ovulation has taken place. In addition, monitoring other symptoms such as cervical mucus changes, can help in determining the fertile days prior to ovulation. This technique of determining basal temperature changes in conjunction with other fertility symptoms, such as cervical mucus changes, is called the SYMPTO- THERMAL METHOD.
The time of ovulation can be used to time sexual intercourse during the fertile days to help increase the chances of pregnancy. This method can also be used to help determine times to avoid sexual intercourse for couples who wish to avoid pregnancy, but it is not as reliable when used for this purpose as it is for increasing the odds of conception.