Basal body temperature is the body temperature measured after a long sleep (6-8 hours) and before waking up, it reflects the energy metabolism level of the body at rest, so it is also called resting body temperature. Basal body temperature can indirectly reflect ovarian function. In the menstrual cycle, with the different secretion of estrogen and progesterone in different periods, the basal body temperature appears to change periodically. The basal body temperature of mature women is slightly lower in the first half of the menstrual cycle, generally between 36.3℃ and 36.5℃, and the lowest during ovulation. Therefore, the basal body temperature of normal menstrual cycle shows a biphasic curve. The anovulatory menstrual cycle lacks the effect of progesterone, and the basal body temperature does not have the above-mentioned regular cycle fluctuations, so it is a monophasic curve. Measurement method of basal body temperature: Patients should measure it by themselves. Every night before going to bed, the mercury column of the thermometer should be thrown below 35℃ and placed on the bedside table or by the pillow, where it can be reached. After waking up in the morning of the second day, do not talk, do not get up, do not move, first take the thermometer under the tongue and take the oral temperature for 5 minutes. It is best to fix the time of measurement every day, usually at 5-7 a.m. Night shift workers should be measured after 6-8 hours of rest, just after waking up. The daily measured temperature is recorded on the basal body temperature sheet and finally drawn as a curve and shown to the doctor during the visit. There is now cell phone software for plotting basal body temperature, which is very convenient. You should record the relevant conditions in your life such as sex, menstrual period, insomnia, cold, etc., and the treatment given on the basal body temperature sheet at any time so that you can refer to it at any time. It usually needs to be measured continuously for at least 3 menstrual cycles or more. Basal body temperature is simple and easy to use, without any damage, and can be determined by the patient. By observing the basal body temperature, the patient’s ovulation time can be understood, and intercourse during ovulation can improve the conception rate. Basal body temperature is one of the most convenient and common methods for monitoring ovulation. Basal body temperature also has other functions: 1, responding to the function of the corpus luteum: the biphasic body temperature with the day of ovulation as the dividing line, which is low in the front and high in the back, shows the normal function of the corpus luteum. 2.Diagnosis of early pregnancy: prolonged luteal phase and basal body temperature rising for 20 days without decreasing are considered to be signs of pregnancy. And when confirmed to be in the first 3 months of pregnancy, if the basal body temperature shows a significant downward trend, it may be a precursor of early miscarriage. 3.Ovulation induction: When ovulation is induced in patients with anovulatory dysfunctional uterine bleeding or infertility, the change in basal body temperature can be used to determine whether ovulation has occurred. 4.Assist in diagnosing the type of bleeding: For patients with irregular vaginal bleeding, the time of bleeding complained of is often difficult to determine the menstrual cycle, and the application of basal body temperature can provide a relatively true and reliable picture of the full menstrual cycle. 5. Response to hypothermia: If the basal body temperature baseline temperature is too high, pelvic tuberculosis and endometriosis need to be considered in gynecologic endocrine patients. Here are some examples for you 1. Basal body temperature profile with normal ovulation: Basal body temperature profile shows standard high and low temperature biphasic changes, i.e. biphasic type of temperature. From the beginning of menstruation to the day of ovulation, the low temperature period is 14 days; after ovulation, the high temperature continues for 14 days, of which the 14th day is the day of ovulation. When the body temperature drops, menstruation will come. 2. Basal body temperature graph without ovulation: continuous low temperature, no high temperature period, no high or low temperature biphasic change. It fluctuates up and down in a certain temperature. 3.Basal body temperature graph of already pregnant: high temperature lasts from the 15th day to the 34th day and lasts for more than 20 days. 4.Basal body temperature graph of suspected early abortion: high temperature lasts from the 15th to the 34th day and then cools down after 20 days, indicating that it is already in pregnancy, but early abortion may occur. 5, poor luteal function temperature drop: If the basic body temperature drops slowly before the next menstrual flow, it indicates poor luteal function. 6, luteinizing hormone concentration is not enough resulting in slow rise in body temperature during ovulation: it can be observed that after ovulation on the 14th, the body temperature starts to rise slowly on the 15th, suggesting insufficient luteinizing hormone concentration.