DuoFertility

For additional information on the DuoFertility product, please see the www.DuoFertility.com website.

DuoFertility is a patent-pending, non-hormonal and minimally invasive passive medical device that allows women to accurately identify ovulation cycles, without daily observation.

Unlike other ovulation prediction kits, with the DuoFertility system there is no need to:

• Maintain consistent sleeping and waking patterns
  (i.e. for example, shift work)
• Wake early each morning (e.g. 4am) to take your temperature, or
• Collect your first urine sample of each morning to measure it, and
• Have your measuring and recording equipment with you every morning
  (which can be a problem if you travel)

We believe that by eliminating these constraints placed on women by existing methods, the reliability of ovulation detection will be greatly improved.

How it works...

Our current prototype devices are about the size of a US dime, 1 Euro cent, or a UK 5 pence piece.

The DuoFertility system consists of a stick-on patch, about 3cm in diameter, which is worn discreetly under the arm. This patch contains a coin-sized circuit that automatically measures and records your body temperature every 10 minutes. When you want to know if you are fertile, you use the hand-held reader, which is about the size of a make-up compact, to read out the temperature data and analyse it, in about 30 seconds. It then tells you whether or not you have ovulated. You consult the reader at your convenience - there is no need to have it with you all the time, and you don't need to do it at any particular time of the day or week.

We have developed and tested our first prototype patches on ourselves with positive results. We are now building test units, which we aim to place with women already trying to conceive. We are always very pleased to hear from women who are interested in what we are trying to do, and if you are interested in being a trialist please fill in our pre-trial questionnaire.

Why do we want to measure temperature to detect ovulation?

When a woman ovulates she is fertile for only a few days. In order to increase the likelihood of pregnancy, it is often advised that this is the best time to try to conceive. It is therefore important to detect ovulation accurately. Ovulation typically causes an increase in body basal temperature (BBT) of around 0.5°C

What is BBT?

Body basal temperature (BBT) is the lowest temperature that the human body reaches in a day. It reaches this "resting" temperature during deep sleep, however most current methods to determine BBT rely on measuring temperature immediately after waking and use this as the best approximation of actual BBT. With the DuoFertility system, temperature is measured throughout the night making accurate determination of BBT much easier.

Why does BBT change around ovulation?

BBT displays a "biphasic pattern" during the menstrual cycle, it is either low or high. BBT is low before ovulation and increases post ovulation, remaining high until menstruation. During the first stage of the cycle prior to ovulation, high levels of estrogen in the body cause a lower BBT. After ovulation, the corpus luteum, a temporary gland created by the ovaries each menstrual cycle, secretes progesterone to create a more fertile environment for the egg. The progesterone causes an increase in body basal temperature until menstruation when the corpus luteum decays and BBT returns to the low state. Some women will also experience a decrease in body basal temperature just before ovulation, which is due to the pre-ovulatory luteinizing hormone (LH) surge inducing ovulation.

What can BBT measurement tell us?

Measuring BBT is very useful in that it can help to detect ovulation to:

• Build a picture of a woman's typical cycle
• Monitor differences between cycles
• Confirm that intercourse occurred when fertility was likely to be high
• Contribute to diagnosis of fertility problems
• Contribute to diagnosis of pregnancy if BBT does not decrease

Studies have shown that the best predictor of pregnancy is high frequency of intercourse during the middle of the menstrual cycle (when ovulation is likely to occur). Using BBT to detect ovulation can help women to understand this variation in fertility.

Does it work?

The theoretical BBT profile over a month.

The data from a commercial store-bought BBT thermometer.

The data from a standard hospital aural thermometer.

The data from our prototype device.

Our prototype devices have undergone initial tests with a small number of women who experience "ovulation pains", so that we know when they ovulate. During one test, we have a volunteer use our prototype device as well as two other devices - a commercial store-bought electronic body basal temperature thermometer and computer, and a standard hospital aural thermometer.

The woman woke every morning at 6:30am, and recorded both her oral temperature using the commercial BBT device, and the temperature of each ear using the hospital aural thermometer, and noted the days of ovulation pains and of first menstruation. This particular woman had a 24-day long cycle this month - the "average" woman has a 28 day cycle, however this can easily vary from 22 to 30 days depending on the woman and from cycle to cycle.

The expected profile is shown at the top, with the progesterone hormone causing an increase in BBT when ovulation occurs, and a decrease in progesterone causing a drop in BBT the day prior to menstruation. The rise indicates that ovulation has occurred, while the absence fall approximately 14 days later is an indication that pregnancy did not occur.

The results clearly demonstrate the superior data collected using our prototype device. None of the other devices show the distinctive "biphasic" pattern expected for a BBT profile, in all probability because the woman's body was not at basal temperature when she woke most days. This is a well known and frequently observed problem with existing BBT measurement systems, which is completely avoided by using continuous measurement in our devices.

The DuoFertility system aims to make BBT measurement easy, accurate and convenient.

Finally, we would love to hear from you personally if you have any comments whatsoever.