Cycle tracker: Is a birth-control app effective?
WE live in a smartphone era, so it’s little surprise that women have started to use fertility apps to help them conceive. Now one of those apps claims to do the opposite by offering an effective form of contraception.
In February 2017, the EU certified the Natural Cycles app as a form of birth control, making it the first app ever to be ranked alongside the pill, condoms, and IUDs.
“Our aim is to provide an alternative,” says Dr Elina Berglund, the 33-year-old Swedish particle physicist -- who was one of the researchers that led Cern to discover the Higgs boson. She designed the app with her husband and fellow physicist Dr Raoul Scherwitzl.
“It was created as a result of my own need to find a natural alternative to prevent pregnancies and give my body a rest from hormones.”
Natural Cycles claims it can pinpoint when you can and can’t get pregnant with 99.5% accuracy under perfect use. But can it really live up to its claims of being comparable to better known methods of contraception?
Like all fertility apps, Natural Cycles is based on fertility awareness. This is a scientific method that involves a woman paying close attention to her body in order to understand her monthly cycle.
Every morning, she takes her basal body temperature (BBT). This is the body’s temperature at rest and it’s best to take it before getting out of bed or moving too much. Because BBT rises when a woman is ovulating, it’s an indicator of fertility.
A woman’s cervical mucus changes around ovulation too. Taken together with other signals, all of these are monitored to give an overall picture of the woman’s fertility cycle.
Women can only become pregnant during the 24 to 48 hours of ovulation and sperm survive in the body for up to five days. This means there are only six days a month where sex can lead to pregnancy. If a woman can identify those six days, she can time intercourse so as to increase or decrease her chances of getting pregnant.
There’s nothing new in this. Austrian gynaecologist Hermann Knaus and Japanese gynaecologist Kyusaku Ogino carried out groundbreaking studies that divided women’s cycles into fertile and infertile days in the 1920s.
Practising Catholics will certainly be familiar with the concept. The rhythm method, still the method of contraception recommended by the Catholic Church, is based on this same fertility theory. However, these same Catholics will also know the rhythm method isn’t always reliable. Does this mean these apps aren’t reliable either?
No, says Berglund. “We have a dedicated team of scientists who have developed an algorithm that women can trust and they are constantly working to make it even better.”
Using a woman’s personal data, Natural Cycles tells her where she is in her cycles. It does so by designating days red or green. Red days mean sex could result in pregnancy. Green days mean no such worry.
“Typically, it takes four to six weeks for Natural Cycles to get to know your body,” says Berglund. “The app is reliable from the beginning though as it gives you more red days until it gets to know your specific cycle. The more data is entered, the more days turn green as the app’s algorithm becomes better able to accurately predict when you are fertile by taking a whole host of factors into account.”
Dr Berglund tested this algorithm herself with the help of a team that included a professor in obstetrics and gynaecology. They carried out several large-scale clinical studies, the most recent of which was the largest ever conducted into fertility awareness methods.
Published in the Contraception journal, it examined data from 22,785 women, with an average age of 29, using the Natural Cycles app for contraception.
The aim was to calculate the app’s Pearl Index — a rate that summarises how many women out of 100 may experience an unintended pregnancy within one year of using a contraceptive method. Natural Cycles was found to have a Pearl Index of 99.5% under perfect use and 93% under typical use.
“What this means is that as long as women act according to whether or not the day is red or green, intercourse is 93% likely not to result in pregnancy,” says Berglund.
This figure compares well with other forms of contraception, with the pill scoring a perfect use figure of 99.7% and a typical use figure of 91%.
These results have led to huge interest in the app.
“We’ve had an incredibly positive response from women looking for natural, non-hormonal, and non-invasive forms of contraception,” says Berglund.
“More than 600,000 women globally — including 6,000 in Ireland — are currently using the app.”
Many are discussing it online. Some are talking about how grateful they are for an alternative to the pill, which in some women can cause symptoms that range from mood swings to weight gain.
Dr Shirley McQuade is medical director of the Dublin Well Woman Centre, where she has seen a growing demand for non-hormonal birth control.
“The only proven effective form of non-hormonal birth control is a copper intrauterine device (IUD) and the number of devices fitted every year has been increasing,” she says. “Between 2005 and 2011, we averaged 65 a year but last year we fitted 292. More women are coming in and asking for it.”
This demand is highest in women in their 20s, according to Dr McQuade. “The copper coil lasts for at least ten years so young women see it as a good choice because they don’t intend to get pregnant until their late 20s or early 30s,” she says. “It’s more reliable than the pill. They don’t need a reminder to take something every day and nor do they have to visit the doctor regularly for prescriptions.”
Copper IUDs also allow women to stay in touch with their fertility cycle, unlike the pill, which creates an artificial cycle. “There is a tendency for women in their late 20s who have been taking contraceptive pills for years to consider having an IUD fitted so they will know what their natural cycle is,” says Dr McQuade.
“They are usually doing this with a view to a possible pregnancy in a few years’ time.”
The Well Woman Centre does not teach fertility awareness, so Dr McQuade does not know if more people are using it as a form of contraception. However, she would not
recommend they do so.
“For committed couples where the woman has a regular cycle, natural fertility awareness claims to have a high level of accuracy but in real life, it has a high failure rate,” she says.
To prove her point, she cites a study published in Trussel et al Contraceptive Technology in 2011 which found that 24% of women had an unintended pregnancy within the first year of typical use of these methods compared with 9% of women taking the pill and 0.8% of those fitted with IUDs.
Dr Bartlomiej Kuczera, a fertility consultant at Beacon Care Fertility in Dublin, believes there are significant limitations to natural birth-control methods.
“In theory, natural fertility compares well with the pill, IUDs, and condoms,” he says.
“However one needs to have a clockwork cycle and lifestyle to have such good results. You have to be keen to make an effort in taking BBT, observing symptoms such as cervical mucus and obeying the rules of abstinence or using condoms on fertile days.”
Fertility apps become problematic because not everyone fits this description. “There are lots of reasons why they might not work,” says Dr McQuade.
“Your cycles could be irregular or shorter than 23 days or longer than 33. You could be menopausal or breastfeeding. You might have polycystic ovarian syndrome. All of these can make identifying ovulation difficult and that’s why I don’t recommend natural fertility methods to anyone looking for effective contraception.”
Dr Kuczera points out that such methods require education and understanding and might not be suited to everyone. “They also require self-discipline and sexually liberal individuals may be unhappy with the limitations,” he says.
Sweden’s Medical Products Agency recently carried out an investigation into Natural Cycles following a report by a Stockholm hospital that 37 women had asked for abortions after becoming pregnant while using the app. The investigation found it was to be expected a small fraction of users of any form of contraception would experience unplanned pregnancy.
Berglund welcomed the investigation’s findings and stands by her app’s effectiveness, stating that she never claimed it was for everyone. “The average user is 30 plus and in a stable relationship,” she says.
“The app tracks their fertility and they can use that information as they want, either to accurately prevent or plan a pregnancy.”
Berglund’s aim is to provide women with a natural alternative when it comes to contraception and hopes her app offers another option for couples who have the desire and ability to abstain or use protection on certain days every month.
She also rejects the criticism voiced by some that these apps place too much of the responsibility for contraception on women.
“The onus of responsibility is shared so the woman inputs her temperature every morning and on red days, when she is fertile, the couple abstain from having sex or use a barrier method like the male condom.”
For those who are looking for contraception by smartphone, there is now an approved app for that but it may not be for everyone.
There’s more than one app for that
Natural fertility awareness forms the basis of all of the fertility-tracking apps on the market. Of those, Natural Cycles is the only one that claims to be a reliable form of contraception. Here’s a list of the most downloaded fertility trackers and what they have to offer:
This app and its wireless basal body temperature thermometer make the process of measuring and tracking your BBT much easier in the mornings. Using this and other signals, it predicts fertile days, ovulation and menstruation.
Using fertility signals such as BBT and cervical mucus, this app alerts you to ovulation dates and the best days to conceive. A bonus feature offers videos, tutorials, and quizzes which help you to get to know your body and its cycle better.
Thanks to its innovative data analysis, Glow’s predictions get better the longer you use the app. What sets it apart from competitor apps is the additional support it offers to those undergoing IVF and IUI treatments.
This app tracks ovulation symptoms from cervical mucus to headaches and allows you to make personalised notes, rather than simply inputting numbers. It also shows your menstruation and ovulation cycles in one display, so you have a full picture for the month ahead.
This app asks you to log symptoms ranging from BBT and blood pressure to your mood in order to make a reliable calculation of your next fertile window. It also allows for syncing between your phone and your partner’s so that you are both on the same page.
The only certified contraceptive app in Europe, this helps you to keep track of your ovulation, your period and the days when sex is likely to result in pregnancy. It claims to get more and more accurate the longer you use it.
