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iCycle: Tracking the Female Cycle

Men often say that women can be very unpredictable, but are they really or is it more a matter of learning how to read a woman’s seasonal forecast? In the old days, the cycle of the moon was said to be linked to the female cycle. Our modern times rely more on technology to get a grasp of the natural tides of the female body. In this blogpost we will introduce some devices that try to help and gain insight into the female cycle. This can be useful when you are trying to get pregnant or want to avoid pregnancy, or when you simply want to learn how to better understand your own or your partner's body, mind and well being. Women who are not on birth control will live in a rhythm of monthly cycles. Every week they pass as it were through another season. Each season has its own characteristics, and affects a woman’s physical well being and energy level and her feelings, emotions and awareness in a different way. Even for women themselves it is sometimes hard to get a grip on their cycle, and to fully understand their own rhythm and to live in harmony with it.

Seasonal forecast

During the first week of a woman’s cycle it is autumn. The female body does something similar to trees that drop their leaves, and cleans up the uterine lining of the womb that did not conceive, in a process that is also called menstruation. During the second week, it is winter. Just like the soil prepares for a new season of life, the female body starts to prepare for the release of a new egg, which is also referred to as the follicular phase. During the third week, spring is in the air, a new vibe, with birds finding mates and sprouts popping out of the soil. The female body releases its egg, which is also called the ovulatory phase. During the last week of the cycle, it is summertime. A time of traveling and adventure, in which everything grows and glows. The egg travels in the womb, the uterine lining prepares for the adventure of welcoming new life by growing bigger. This phase is also referred to as the luteal phase. And then either winter returns or… the first signs of new life put the female seasonal cycle upside down...

The number of devices and apps that claim to help women with tracking their seasons, has grown rapidly in recent years. They include everything from apps that are in essence fancy, electronic versions of period tracking beads bracelets based on the calendar method, to more advanced devices, based on vital signs tracking, that give a far more accurate idea of a woman’s fertility window. Below we shed some light on three devices that have been introduced fairly recently or are a household name that kept developing their product to keep competing in an innovating market. Please bear in mind that the selection is necessarily arbitrary, and that their inclusion here is not an endorsement nor a conclusive evaluation of their pros and cons or a validation of their effectiveness. Although as a midwife I don’t mind assisting in a delivery, I cannot be held responsible for any pregnancies that do (or do not) result from the use of these products… ;-)

One final remark concerns the involvement of commercial third parties in the development and exploitation of the devices and apps concerned. As this Guardian-article shows, the underlying business concepts might be less innocent than they seem in on first glance. The health information collected through apps and self monitoring may be used to strike deals with the pharmaceutical industry and parties in the field of reproductive health techniques. Whether these deals primarily serve the interests of the users who provided the information, might be questioned.


Ava is a bracelet that helps women to get insight into their cycle and track their fertile days. The bracelet is worn at night and measures pulse rate, breathing rate, heart rate variability, sleep duration and sleep phases, movement, skin temperature, heat loss, perfusion, and bio-impedance. In the morning, the bracelet is synchronised with a smartphone app (available for both iOS and Android) based on algorithms that calculate the fertile period. Apart from that, it also gives insight into health indicators such as sleep, stress levels and heart rates. Ava claims that its device “detects an average of 5.3 fertile days per cycle at 89 percent accuracy”.

Ava can be used by women with cycles ranging from 25 up to and including 34 days, regardless of whether they are regular or irregular. The company warns that the testing of the device did not include women with hormonal conditions that interrupt ovulation (for example PCOS or hypothalamic amenorrhea), and that it will not work for women whose normal ovulation has been blocked by scarring due to severe endometriosis.

As of July 2016, the first batch of Ava bracelets became available for sale in the United States. Since January 2017, it is also for sale in Europe. Judging by the customer reviews on its website, Ava was generally received well. Some critical remarks were made, however, and the biggest complaints of the first users seemed to concern the fragility of the bracelets strap and clasp, which occasionally led to the Ava falling off during the night. In October 2016, Ava announced that it was working on a redesign.

A final remark concerns Ava’s life span. The device’s rechargeable battery cannot be replaced, but, says the company, “when used properly Ava should last several years”. What “several years” means, remains unclear. At a price of € 249,-, this makes it hard to judge whether the Ava is a sustainable buy.


The Lady-Comp has been used for over 28 years now. The device has established itself as a household name and has been updated regularly. Lady-Comp determines the fertile days based on a rise in body temperature. To put it simply, a woman can get pregnant in the 24 hours after her egg is released from the ovary (also called ovulation). Ovulation comes with a slight rise in body temperature. The problem however is that the rise can only be observed when you measure daily, and that you are already fertile at the moment you notice the shift. Research shows that sperm cells can live up to five days in the female body, which means that sperm that entered the body days before the ovulation can still fertilize an egg immediately after its release. In other words, a woman can get pregnant by having sex in the whole period from 5 days before ovulation up to and during the 24 hours of ovulation.

Being able to predict the moment of ovulation is therefore key, and that is where the Lady-Comp can be of help. Every morning, before getting out of bed, the body temperature is measured with a sensor under the tongue. The Lady-Comp processes the data and is capable of recognising individual fertility patterns. It has a pre-stored algorithm of 900.000 cycles that is used as a reference. The outcome is indicated by a traffic light system: a red light for fertile days, a green light for infertile days and an orange light for when it is unclear. The color that lights up is valid for the next 24 hours. For a demonstration, take a look at this video.

The company claims that clinical studies have found an effectiveness “ranging from 99,36% to 99,5%”, and that the reliability will not be affected when a measuring is skipped. On their website the company explains why the Lady-Comp is based solely on temperature readings, without additional features like observing mucus discharge or intermenstrual pain. According to them, these have not proven to add to the reliability and would rather create more insecurity and even reduce contraceptive safety.

Lady-Comp says the device can be used by women with irregular cycles or with conditions such as Hashimoto’s disease and hyperthyroidism and that to be able to use it, no minimum or maximum cycle length is required. Furthermore, they also claim that women working irregular hours, waking up during the night, traveling through time zones or close to their menopause can also use the Lady-Comp. When regularly taking medication that influences the body temperature, using the Lady-Comp is contra-indicated.

The Lady-Comp is powered by an integrated rechargeable battery. According to the company, the device’s internal memory stores all data safely, even in the event of an accident or power failure. Currently, the Lady-Comp comes in four models: the standard version (€ 457,-), a simpler version called the Lady-Comp Basic (€ 364,-), the travel and handbag friendly Pearly (€ 306,-) and the pocket size Daisy (€ 295,-), that can be used as a stand alone or in combination with the app daysyView that provides cycle details. A comparison of Lady-Comp’s products can be found here.

The Lady-Comp can be updated to a Lady-Comp Baby by inserting an SD card (€ 86,-) that contains statistical methods and conception planning software. This allows couples to register intercourse, to observe when no ovulation takes place, when there is a risk of an early miscarriage or when a woman has a hormonal imbalance. Besides, it comes with a gender prediction option, a pregnancy confirmation option and an expected due date calculator. These last options raise an eyebrow, since somehow it seems unlikely that a device like the Lady-Comp would be capable of making accurate predictions in these matters. I would love to see something more on their technical and scientific foundations on the Lady-Comp website.


Wink is basically an oral thermometer developed to help women map their cycle and predict their fertile window. It was devised by the Kindara company, and is specifically meant to be used with the Kindara app. Women can use the Wink to read their body temperature every morning at the same time before they get up. Both the temperature and the time of reading are automatically synchronised through Bluetooth with the Kindara app (available for Android and iOs).

The app then charts these data and asks for several others to be added, the most important of which seems to be the consistency of the cervical fluid. Other options allow women to chart their periods, moments when they had sex, and additional data that might help to gain insight into their cycle (such as acne breakouts or ovulation pain). There is also the possibility of getting in touch with experts that can answer questions and with a community of other women using the app. The Kindara app is available for iOs and Android and can be downloaded for free. The Wink costs € 121,- and is charged through a micro-USB cable.

Wink and the Kindara app can be used to get pregnant or to avoid pregnancy. Kindara, the company says, “is based on the Fertility Awareness Method”, which is often used as a collective term for natural family planning methods like the calendar method, the cervical mucus method, the basal body temperature method or the sympto-thermal method (which combines the previous methods with other body symptoms). All these methods have in common that they try to define when you are fertile and when not.

“When used correctly, with a clear understanding of your cycle and a thorough understanding of the rules, Fertility Awareness is shown to be 99.6% effective for avoiding pregnancy.” The app can also function as a means for women to keep an eye on their gynaecological health (to identify for instance PCOS, hyper/hypothyroidism and endometriosis) and, for adolescent girls, their future general health.

Rocket science?

When reading about devices like the ones described here, please bear in mind that nature can sometimes be quite unpredictable and that the female seasonal forecast is not always rocket science. Every method has its strengths and limitations, its pros and cons, and there can be quite some difference between results from test settings and those from use in daily practice. If you want to crack the code of a female cycle, you first need to deeply understand the female body, the particular woman involved and what she is going through. Simple things like flying and crossing time zones, insomnia, stress, the flu et cetera can already impact a cycle, let alone psycho-social, emotional and relational components.

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Lady-Comp, see: Check the user video here:

Wink & Kindara app, see: Moira Weigel. ‘Fitbit for your period’: the rise of fertility tracking. The Guardian, 23 March 2016. See:


Afbeelding 1: CCBY Frank Monnerjahn, see:

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