Should You Try a Natural Family Planning App for Birth Control?

In August 2018, the U.S. Food and Drug Administration made a landmark decision when it allowed the natural family planning application known as Natural Cycles be used as a form of contraception. Up until then, the app, which uses an algorithm to calculate when a woman is most fertile during the month, was recommended for women who were trying to become pregnant. Now, it can be used as a natural form of birth control.

Like many other apps of its kind, Natural Cycles requires that the user take her temperature daily using a basal body thermometer and plug in the reading, along with information about her menstrual cycle, into the app. The app then determines when a woman is most likely to conceive, displaying "use protection" on those days, and "not fertile" on the other days of her cycle.

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When used perfectly, the natural family planning app has a failure rate of almost 2 percent, meaning that two women in 100 become pregnant when they use the app for a year. For the average person, the failure rate hovers around 7 percent.

Considering opting for an app for birth control? Here's everything you need to know about NFP apps.

NFP Isn't New

Although natural family planning (NFP) apps are a relatively new thing, preventing pregnancy through fertility awareness has been around for centuries. Couples have adopted some form of NFP for reasons that range from adhering to church doctrine, some of which prohibits the use of artificial birth control, to avoiding synthetic hormones and their side effects.

NFP is a chemical- and device-free form of contraception that involves tracking a woman's fertility cycle, and and avoiding sex or using alternative birth control like condoms on the days when she is most likely to conceive. To determine that fertility, there are three main methods, which can be used individually or in combination. They include recording the length of your cycle, measuring your basal temperature, and tracking the consistency of cervical mucus.

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Because daily tracking can be cumbersome, companies have introduced digital apps to make it easier, although it still requires commitment on the part of the user and experts agree that it's important that you clearly understand the method. In addition, some NFP apps are simply a way to record observations but offer no fertility predictions.

The Best Apps for Natural Family Planning

Like Natural Cycles, which still remains the only app with FDA approval for pregnancy prevention, other apps also make predictions. Among the more well-known apps include Clue Period Tracker, which includes an ovulation calculator to determine your menstrual cycle; Flo Period and Ovulation Tracker, which uses machine learning to make its predictions; and Glow Period and Fertility Tracker, which allows you to record other symptoms, such as mood.

Other apps that simply help with the tracking, but make no predictions, include Kindara, which features one of the first digital charting systems and also comes with a wireless basal body thermometer; and NFP Charting, which can only be used if you have training with a specific form of fertility awareness based method known as the Billings ovulation method.

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Natural Family Planning Charts vs. Apps

While using these technologies might help streamline the tedious charting process, some health professionals caution against being too confident in the technology. For example, some of the apps use their own proprietary algorithms to predict fertility, and those algorithms have not been peer reviewed. Other apps may not factor in the possibility of a woman having an irregular cycle.

"Even women that typically have regular 28 to 30 day menstrual cycles can have the occasional irregular cycle due to stress, illness, medications, etc," says Christopher Carrubba, M.D., a physician of internal medicine and a healthcare entrepreneur in Jacksonville, Florida. "In that situation, they may be at a higher risk of pregnancy if using the app."

Dr. Carrubba says those using these apps need to do so cautiously, even if they do have FDA approval.

"For many patients, the logic would be that if the FDA has approved it, then it must be as good or better than the other options out there, and I just don't think that is true," says Dr. Carrubba. He says that the FDA approval was based on a controlled trial of roughly 15,000 women, but that in the study, the patients had more instruction and oversight than would be expected in a real-world setting.

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"We are already seeing some concerns with this," says Dr. Carrubba. "In Sweden, around three dozen women using the app have reported becoming pregnant. That doesn't surprise me given the room for user error with an app."

But he does admit it is another option for those who may not have as many available to them.

"Not all patients can use IUDs or oral contraceptives given that there are medical contraindications for some patients or religious beliefs that limit or prohibit the use of birth control," says Dr. Carrubba. "Some patients may also have side effects with medical contraception options. In those cases, I do think an app like Natural Cycles would be a better alternative to the rhythm method or [the withdrawal method]."

The Bottom Line

With this kind of technology, you should proceed with caution, and talk to your doctor before using it.

"The company states that it's not for anyone who would be devastated by a pregnancy," says Felice Gersh, an OB-GYN and the founder of the Integrative Medical Group in Irvine, California. "It's best used by a woman wanting to space her children."

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