How does DuoFertility work

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How does DuoFertility work

If you are trying to get pregnant then DuoFertility could help you determine the most fertile days of your cycle.

Published 07/01/2011

If you are trying to get pregnant, learn more about your ovulation cycle with DuoFertility.

Everyone's journey to getting pregnant is different. Whether you have been trying to get pregnant for just a few short months, you have an irregular monthly cycle, or have been trying to conceive for a significant period of time, understanding your most fertile days may help.

The DuoFertility monitor can help maximise your chances of getting pregnant naturally. It uses a sophisticated version of the body basal temperature method to identify the period in your monthly cycle when you are most likely to get pregnant, up to six days in advance.

Basal body temperature is the lowest temperature attained by the body during rest (usually during sleep). It is generally measured immediately after awakening and before any physical activity has been undertaken, although the temperature measured at that time is somewhat higher than the true basal body temperature.

A woman tends to have a lower temperature before ovulation and a higher temperature afterwards. Ovulation causes an increase of one-half to one degree Fahrenheit (one-quarter to one-half degree Celsius) in basal body temperature and therefore monitoring basal body temperature is one way of estimating the day of ovulation.

How does DuoFertility work?

The DuoFertility ovulation monitor consists of a small sensor and a hand-held reader. The sensor is attached to an adhesive patch, about 3cm in diameter, which is worn discreetly under the arm.

It records temperature continuously and determines when ovulation occurs using a sophisticated version of the basal body temperature method.

The sensor automatically measures and records skin temperature, taking approximately 20,000 temperature measurements while the wearer is asleep. This allows easy detection of the upward shift in basal body temperature associated with ovulation.

The technology has been shown to be 99% accurate at detecting the most fertile days of a woman's cycle, and unlike other methods, has completely eliminated the need to wake up early to take temperature measurements.

What happens next?

The data is then transferred wirelessly from the sensor to the DuoFertility reader. The reader then provides a simple fertility status for the next six days. The reader can be consulted any time - it's not necessary to use it at any particular time of the day or week.

The DuoFertility reader can also combine the temperature measurements collected by the sensor with additional data recorded, such as cervical mucus quality and the date of menstruation. This allows the monitor to determine the day of ovulation even more precisely, with tests recording 99.7% accuracy.

Even more information is available when the DuoFertility reader is connected to a PC. For example:

  • Temperature data can be shown visually.
  • Couples can add or edit more fertility information.
  • In-depth reports about your cycles can be requested from one of DuoFertility's fertility specialists.

Remember, the DuoFertility experts are on hand to support you in your journey to pregnancy. This is a free personalised service to maximise your chances of getting pregnant naturally. You can contact them via email ( or telephone (+44 (0) 1223 437 001) between 9am and 8pm. Callers after 8pm can simply leave a message and the DuoFertility team will be in touch the next day.

If you have been trying to conceive for some time, it may be helpful for you to discuss using DuoFertility with your doctor.

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