Medically reviewed by Leah Millheiser, MD
Written by Our Editorial Team
Last updated 10/10/2019
In the last 20 years we’ve seen a shift in the way people are choosing to take care of themselves — for the better. People everywhere are slowly coming to terms with their health in ways we’ve seldom seen before, from making healthier dietary and lifestyle choices, to ramping up interest in fitness, education and everything in between.
Media and technology companies caught on and adopted conscious health-driven content. Headspace is one of the leading meditation apps on the market with over 30 million downloads, respectively. Netflix released a small lineup of films last year all related to the impact of food production — most notably their series Rotten, potentially the reason why 30 percent of our friends went vegan for three months last year.
And more recently, we’ve seen a slew of “period apps” cropping up whose missions are to help us figure out when we’re menstruating, when we’re ovulating and what we can expect from our bodies on a monthly basis. If we’re using apps to help us make healthier dinners, create better work outs and find enlightenment through meditation, why not use an app to help us understand our reproductive cycles?
Phone apps were listed as the number one method for menstrual tracking in a recent study published by DUB Group from the University of Washington. According to the research team, the study is one of the first of its kind, investigating how and why women track their menstrual cycles.
Using a mix of over 685 survey respondents, over 10 interviews and an analysis of over 2,000 reviews from a slew of different menstrual tracking apps, the team put together a wide sample group of participants with different gender identities and sexual preferences, as well as an age range of 13 to sixty.
According to the researchers, nearly 70 percent of U.S. adults are tracking one form of health related issue, whether it be on Apple’s HealthKit, their Fitbit or some other app or device.
In the multitude of apps for women that are available, some of the most downloaded are Clue with over 8 million users, Flo with 26 million monthly active users and Glow with 15 million users. The apps are designed to track female reproductive cycles so you can determine when you start menstruating, when you’re ovulating and what your mood levels or PMS symptoms may be.
Generally, period tracking apps work based on data input by users. Users must enter the start date and duration of menstruation, and generally must continue doing so for at least three months before an app can give an accurate analysis of a user’s ovulation cycle.
For further analysis of your overall physical health, some apps also have other data inputs for things like sleep and dietary habits, pre-existing pain, exercise norms, hair type, body temperature and weight.
In the study mentioned above, women listed wanting to better understand their bodies and menstrual cycles as the main reason for using the apps. However, many women are using the apps as an alternative form of contraception, noting when they are ovulating and when their risk of pregnancy is highest.
A Swedish-made app, Natural Cycles, brands itself as “The First and Only Birth Control App” and as a form of “hormone-free birth control.” It’s a bold statement, but the app is the first of its kind to gain approval by the U.S Food and Drug Administration, putting it in the same category as classic forms of contraception like hormonal birth control and IUDs.
The app works similarly to other period tracker apps for the most part. Users must input their menstrual data, along with a daily reading of their temperature (via basal body thermometer). That information is plugged into an algorithm that tells women when they’re fertile, when they should consider using protection or when there’s little to no risk of pregnancy.
According to studies of the Natural Cycles app, under “normal use” conditions, it’s 93 percent effective as a contraceptive method. Under perfect use conditions, it’s 98.2 percent effective.
For those keeping score at home, that’s about as effective as most hormonal birth control, which is generally 93 percent effective under normal use and 99 percent effective with perfect use; more effective than diaphragms and other barrier methods of protection, which are 83 percent effective; about as effective as the birth control patch, which is 93 percent effective; and less effective than the queen of birth control methods, the IUD, which is over 99 percent effective on average — according to the CDC.
The one thing all these apps have in common is that their effectiveness is based solely on the information their users are inputting. If users inaccurately log the information or only input part of the data required to analyze their cycle, the app’s effectiveness drops dramatically.
There are also many other data factors that the app doesn’t have input options for, including whether you’re using some kind of birth control, have taken a form of emergency contraception, etc. There are no options within most — perhaps all — of the free period tracker apps to input this sort of data, rendering them non-inclusive to women who have experienced any of these issues.
The DUB study above also investigated the shortcomings of the apps — from design to inclusion — noting that many of the apps don’t take into account users’ sexual preferences, cycle stage (not taking into account women who may be entering their menopausal stage) and women with conditions such as endometriosis or women who have irregular periods.
Spot On, a gender-neutral period tracking app from Planned Parenthood, aims to be a “nonjudgmental” alternative for the period app market. However, even Spot On warns their app isn’t perfect: “Fertility features in Spot On are designed to support Fertility Awareness Methods, and should not be relied on to prevent pregnancy as ovulation can change from month to month.”
Another, more natural issue with the “Fertility Awareness Method” (and the apps people use to track them) is that ovulation isn’t a precise science.
Women’s reproductive cycles usually run on a 23- to 35-day cycle, and while there are always exceptions, most women's cycles fluctuate. Day one of your cycle is the first day of menstruation, the first day you bleed. Typically, 15 to 18 days after the first day of menstruation is the period when women are most fertile. However, there’s really no telling how accurate that information is.
Another factor to consider when tracking your ovulation as a mode of contraception is that following ejaculation, sperm can “survive” for several days. So, even if you’ve planned everything just right, it’s still possible to get pregnant after unprotected sex.
The truth is, all contraceptive methods are different, and it’s up to every woman to make the conscious decision to choose the best one for them. The IUD is still — by far — the most effective form of contraception. But it’s also invasive.
Hormonal birth control can be 99 percent effective if used perfectly, but when’s the last time you remembered to take all your birth control pills at the same exact time, every single day?
And let’s not forget about sexually transmitted infections; the only contraceptive out there designed to help prevent them are condoms, which are less than 90 percent effective under normal use (oof!).
Are period tracking apps the future of birth control? Probably not. But if you want to have the most accurate map of your menstrual and ovulation cycles, they’re a great tool to help women figure it all out.
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