What is the Basal Body Temperature?
Your basal body temperature is your temperature when you are fully at rest. Its significance in relation to ovulation and pregnancy was first recognised by the German priest Wilhelm Hillebrand in 1935. Based on the findings of the Dutch gynaecologist Van de Velde and the calendar method of birth control developed by Ogino and Knaus, he produced the first temperature-based method of birth control. Since then it has been used by generations of women as way of identifying their ovulation and the best time to get pregnant.
Hormonal Influence on your Basal Body Temperature
The menstrual cycle begins on the first day of a woman´s period. The phase of the cycle before ovulation is called the follicular phase and during this time the higher levels of oestrogen cause the basal body temperature to fluctuate within a lower range. The second phase of the menstrual cycle begins at ovulation and is called the luteal phase, during this phase the higher levels of progesterone cause the basal body temperature to fluctuate within a higher range. The higher levels of progesterone in the luteal phase are released by the corpus luteum, the remains of the ovarian follicle that released a mature egg during ovulation, this minute rise in basal body temperature is as a direct result of ovulation and is a reliable indication that ovulation has occurred.
Using the Temperature Method
Although the science behind the basal body temperature is solid, it has, up till now, been considered too inexact and difficult to implement accurately. It is extremely difficult to measure the basal body temperature exactly and even more difficult to spot the minute (0.2° - 0.5°C) rise in basal body temperature caused by ovulation. Measuring with a thermometer involves taking your temperature every day at exactly the same time and place, before you get out of bed, charting this information for the whole month while remembering to take disrupting factors such as alcohol consumption, sleeping patterns or sickness, into consideration.
How femSense can help
The technology behind the femSense sensor patch finally makes the temperature method exact and easy to use. The patch measures your temperature up to 5000 times during your fertile window, giving femSense temperature curves which can be compared over several days resulting in very precise measurements and accurate ovulation identification. The patch is applied several days before the predicted ovulation and only needs to be read once a day, freeing you from the restrictions of measuring at the same time and place and the worry about whether insomnia or getting up during the night will affect your reading.