The calendars (or e-calendars) for monitoring the menstrual cycle and fertility are blooming on the Internet, on the AppleStore and on Google Play: from Clue to Flo Period Tracker, via "Rule Tracking" or "My Ovulation".
It is usually sufficient to enter the start date of our rules and the average duration of our cycles to obtain a provisional calendar of our next ovulations and menstruation.
Some applications also offer to record other intimate information, such as monitoring the temperature or the appearance of our cervical mucus, while others offer little more: advice or alerts of the type "Ovulation in 4 days" or " Your rules are coming tomorrow. "
The menstrual calendar, a logbook with limited effectiveness
Ovulation usually occurs 14 days before the next period . As the life of an egg does not exceed 24 hours in theory and that of sperm lasts 3 to 5 days on average in the female genital tract, the fertility period begins four days before ovulation and ends a day later.
If our menstrual cycles are very regular, it is easy to predict.
But if we are not set like a clock, difficult to estimate the first day of the rules ahead, and therefore the next window of fire to maximize the success of our baby project.
Without additional details, such as the consistency of mucus, "e-calendars are in this case of poor utility," agrees Daniel Epstein, researcher in digital optimization at the University of Washington.
Only 13% of women have extremely regular cycles, 28 days systematically.
Application "My menstrual calculator"
No, a menstrual calendar does not prevent you from getting pregnant
Many women use calendars to avoid getting pregnant, taking care to avoid sexual intercourse on so-called fertility days.
But if there is an optimal period of fertility, believing that every other day of the month is a period of total infertility is a serious mistake: you can get pregnant at other times in the cycle, even in periods of menstruation!
Some particularly tough sperm manage to survive up to a week in the fallopian tubes or in the uterine environment.
And it also happens that an egg is still fertile two days after ovulation. When one of our cycle is very short (21 days), it may well ovulate shortly after our rules (from the 6th day) and therefore get pregnant if we made love during our menstruation.
What happens to the personal data of these calendars?
These girly apps brew all the information given by their users. Since many do not just report their cycle phases, but also specify their age, weight, mood, or date of last intercourse, many sensitive data go into the hands of app managers.
Are they well protected? According to a report on these women's applications * of the Electronic Frontier Foundation, an American association for the defense of digital freedoms, "there are security holes".
"Women's health is a big business that arouses envy."
This is particularly emphasized by Quintin, the lead author of the study. These applications are fun and useful in some cases, but we must remain vigilant because they do not have a clear data protection policy. "
This is enough to whet the appetite of marketing companies and manufacturers wishing to broadcast targeted advertising (for hygienic protections, pregnancy tests ...). Especially since the economic model of these apps - often free - relies on the use of collected data or advertising targeting.
Before creating a menstrual tracking account, we read the "privacy policy" of the selected app.
In addition, we refuse synchronization with our camera or geolocation, and we lock our data with a strong password. Or opt for an open source application (such as Periodical) that does not need to be connected to the Internet and backs up data locally, not on central servers.
* www.eff.org/files/2017/07/27/the_pregnancy_panopticon.pdf
