Science behind it
The DuoFertility monitor, a revolution in Temperature measurment
Body basal temperature (BBT) is the lowest temperature that a woman’s body reaches during each 24-hour day. This “resting” temperature is usually reached during deep sleep and then increases as she wakes up.
Why BBT?
BBT is the oldest method of fertility monitoring and was first used in the 1930s. It is a well-established and trusted method of ovulation detection.
How Does BBT Change Throughout the Menstrual Cycle?
Women’s BBT patterns are biphasic i.e. they consist of two different phases during the menstrual cycle. The temperatures taken in the first phase before ovulation are lower than those taken in the second phase after ovulation. The average temperature prior to ovulation is 36.37 ºC and after ovulation is 36.72 ºC although this varies from woman to woman and cycle to cycle. This small increase in BBT will occur within 48 hours of ovulation and will remain elevated until her next period.
Why Does BBT Change?
During the first phase of the menstrual cycle, high levels of oestrogen in your body keep temperatures low. The raised BBT after ovulation is due to the high level of progesterone in the body. Progesterone is secreted by the corpus luteum (the empty egg sac that the egg emerges from) and indicates that ovulation has occured. This is why measuring BBT is the only method that actually confirms ovulation.
Current Methods of Measuring BBT
Traditional methods of recording your BBT involve taking an oral, rectal or vaginal measurement at the same time each morning. These measurements must be taken as soon as a woman wakes as even the act of waking or getting out of bed will increase her temperature, leading to inaccuracies in the measurment. As a result, these methods tend to generate “noisy” data, which can be confusing when trying to identify such a small change in temperature. Therefore most of these methods abide by the 3 over 6 rule – ovulation can be confirmed if 3 high temperatures following 6 low temperatures are observed. However, confirmation that ovulation has occurred 3 days after the event is too late to take action, as the egg only survives for up to 2 days.
DuoFertility Revolutionises BBT Monitoring
DuoFertility combines new advanced technology with a traditional and trusted method of ovulation monitoring, to accurately identify her most fertile days.
By simply wearing the DuoFertility sensor under her arm, it will take 20,000 temperature measurements throughout the day and night to provide the most accurate temperature for that day.