A Woman's Cycle
Only 10 - 15% of women have cycles that are exactly 28 days in length.
Every woman has her individual cycle
The menstrual cycle varies individually from woman to woman. The menstrual cycle begins with the first day of bleeding, which is counted as day 1. The cycle ends just before the next menstrual period. An average cycle is assumed to be 28 days. Some women may have shorter (25 days) or longer (36 days) cycles.The computer will use this personal cycle pattern as a basis for its calculations. After some time, if the user has regularly entered her daily temperature, the computer will know that this particular woman will ovulate on day X of the cycle and her monthly period will start after X days.
Basal Body Temperature
Lady-Comp uses its high-precision temperature sensor, the highest in the world, to pinpoint your ovulation. Ovulation causes a slight, but easily detectable increase in the body temperature. Likewise, the temperature will drop back to normal when menstruation begins (defined as the beginning of a monthly cycle). This is the pattern on which the computer bases its calculations to specifically filter out the six days of a cycle when intercourse could lead to pregnancy. In this time you are free to choose whether you abstain from sex, if you use a barrier method of contraception or if you plan a baby.
The 3 phases of the menstrual cycle
- The infertile phase at the beginning of each cycle
- The fertile phase around ovulation
- And the infertile phase after ovulation to the next menstruation
Hormones and Temperature
The above graphic illustrates the individual processes of the female monthly cycle and shows how they are reflected in the temperature curve. To make it easier we use an average 28 day cycle, where ovulation takes place on the 14th day.
During your monthly menstrual cycle, two hormones race through your system. During the first half of your cycle (called the pre - ovulatory phase from day 1-14) estrogen is the star. Estrogen helps your ovaries produce an egg that is released during ovulation. During the second half of your cycle (the post - ovulatory phase), progesterone takes over. Progesterone will dominate until it falls in anticipation of your menstrual period.
See how the pink dotted line (at the bottom of the graph) represents the basal body temperature course? As you can see the temperature increases during ovulation very slightly by just 0.25 to 0.45 degree Celsius.
LadyComp's high-precision temperature sensor, the highest in the world, can accurately detect the smallest temperature increase.
With that background, it's easy to explain the theory behind Lady-Comp. Estrogen is a "cool" hormone. Progesterone is "warm". Prior to ovulation, when estrogen is dominant, your body temperature is marginally cooler than after ovulation, when progesterone is in charge. Given these facts, an increase in basal body temperature indicates that you have ovulated.