Ultrasonography is an accurate and intuitive ovulation test for pregnant women. But going to hospital is time-consuming and unnecessary. In fact, if you make good use of our "basal body temperature," you can accurately calculate the date of ovulation by monitoring it at home.
Basal Body Temperature is when the body is awake and not affected by muscle activity, mental stress, food and ambient temperature. It is also known as "Basal Body Temperature"(BBT). Basal body temperature is usually measured before getting up in the morning. The basic body temperature of women varies with the menstrual cycle. The body temperature is low during the follicular period, lowest on ovulation day, and rises 0.3~0.6℃ after ovulation.
Menstrual cycle, can be referred to as cycle, starts on the first day of bleeding with female menstruation and ends on the beginning of the next menstrual cycle. The length of the cycle varies from person to person, ranging from 21 to 35 days, with an average of about 28 days.
Typically, a woman ovulates only once a cycle, and the day of ovulation is called ovulation day.
The menstrual cycle of a woman is divided into the follicular period before ovulation and the luteal period after ovulation. The next day after ovulation, because the ovaries form luteum, the secretion of progesterone will make the basic body temperature rise about 0.3-0.6℃ and the temperature will continue to rise until the next cycle which is before the beginning of 1-2 days.
For the normal ovulation cycle of women, the cold phase starts one or two days before menstruation, and continues until ovulation day, then enters the hot phase for a day or two, next dips again into the cycle after the start of her next period. In each menstrual cycle, the basal body temperature shows low temperature phase and high temperature phase with ovulation day as the demarcation point. So it is called biphasic basal body temperature.
By contrast, if a woman does not ovulate in one cycle, her basal body temperature does not show biphasic changes, which is called uniphasic basal body temperature. So uniphasic body temperature means anovulation.
As mentioned above, a woman's basal body temperature is at its lowest on ovulation day, which means the point at the cold phase meets the high temperature phase. After basal body temperature monitor measuring the temperature of a menstrual cycle, we can draw the basic body temperature curve according to the temperature value and find the junction point of low temperature phase and high temperature phase, so we can clearly know our own ovulation day!
The method of "6 low and 3 high" is to check whether the basic body temperature has a biphasic body temperature curve. We can confirm the ovulation date of a woman according to this method.
The so-called "6 low and 3 high" method means that, starting from the first day of the whole cycle, the data are compared with the previous 6 body temperature data every day (abnormal invalid temperature data are deleted), and the previous 6 groups of data can be drawn a highest comparison line for clear comparison. If the data of this day, the second day and the third day are all higher than the comparison line, and the data of the third day is at least 0.3℃ higher than the data of the previous six groups, then this day is indicated as the beginning of the high temperature period of the basal body temperature, and this day becomes the "warming day", and the day before the "warming day" is called the "ovulation day".