Natural Family Planning Methods Can Work, But They Take a Big Commitment

Martha Kempner

The Pope drew attention to natural family planning methods when he suggested there are ways for Catholic women to limit the number of children they have without violating the Church's teachings on contraception. But just how do these methods work? And how good are they?

After the Pope’s recent trip to the Philippines, as Rewire reported, he had some advice for Catholic women about family planning: He suggested that there are “acceptable solutions” for couples, so they don’t have to “be like rabbits” and have lots of children. Given the Catholic Church’s prohibition on modern contraceptive methods, however, those “many acceptable solutions” likely boil down to natural family planning.

Once called the rhythm or calendar method, natural family planning at its simplest refers to tracking a woman’s cycle in order to determine her most fertile days and avoiding sexual activity or using a backup method during that time. Today, there are many different methods for doing so, all covered under the umbrella term of fertility awareness-based (FAB) techniques. Some are as simple as counting days and estimating the middle of the cycle—when most women are likely to get pregnant—while others require taking one’s body temperature every day and checking cervical secretions. Though there are a number of low- and high-tech tools (from beads to apps) that women can use, doing this right takes patience and commitment. And, of course, it does not protect against sexually transmitted infections (STIs).

Though FAB methods should be a choice for women—especially those who have decided for whatever reason that they are not comfortable with their other options—it seems clear that the Pope doesn’t understand how difficult and limiting these methods can be.

Counting Days and Calculating Risk

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There are only six days during any menstrual cycle that a woman can become pregnant. Most women release one ovum each month, which is only viable for fertilization for about 12 to 24 hours after it is released. Sperm, meanwhile, can live in the reproductive tract for three to five days. The six-day window, therefore, is comprised of the five days before and the day of ovulation.

The tricky part, of course, is determining when ovulation is about to happen—because those are the most unsafe days. According to Contraceptive Technology, 78 percent of menstrual cycles are between 26 and 32 days long; for most women, ovulation occurs right around the middle. If “day one” is the day a woman starts menstruating, most can assume that ovulation occurs somewhere between day eight and day 19.

The easiest FAB method, called the Standard Days Method, is based on this model of ovulation. It requires only that a woman keep track of the first day of her most recent period. Then she counts forward and either abstains from intercourse or uses a back-up method from day eight to day 19.

One popular tool for helping women use this method is called Cycle Beads, essentially a necklace made up of beads of different colors. Women mark the first day of their period by sliding a ring onto the first red bead. They then move the ring forward one bead every day. Days eight to 19 are symbolized with white beads, when women should avoid unprotected sex. When they reach the brown beads at day 20, sex is safer again.

While the Standard Days Method is relatively simple—with or without the beads—it requires 11 days without unprotected sex. Moreover, it only works for women with regular cycles that fall within the 28- and 32-day range.

Another, more specific, method of counting days is called the Calendar Rhythm Method. Before starting this method, a woman must track the length of her cycles for six months and then do a few math problems in order to account for fluctuations in ovulation time. First, she subtracts 18 from the number of days in her shortest cycle, giving her the first fertile day of her current cycle, then she subtracts 11 from the number of days in her longest cycle, which gives her the last fertile day. So, as an example, if her shortest cycle lasted 28 days and her longest cycle lasted 35, she would consider day ten to day 21 to be unsafe. This math has to be redone each month to get the most accurate results for the current cycle.

Monitoring the Body for Signs of Ovulation

For truly accurate results, however, a woman—especially one who has irregular cycles—should keep track of her body’s signs of ovulation too. Before ovulation, women secrete clear, stretchy, and slippery cervical mucus. From an evolutionary standpoint, our bodies are designed to promote pregnancy; these mucus properties can propel sperm toward an egg.

Proponents of one FAB method, called the TwoDay Method, tells women to check for secretions a few times every day by examining their underwear, looking at toilet paper they’ve used, and feeling their vulva. If they notice any secretions they should abstain for two days. Of course, a woman may have to abstain for more than one two-day period using this method because she may have secretions during her cycle that are not actually a signal of imminent ovulation.

More complicated and more accurate versions of this method ask women to look for not just the presence of mucus but its characteristics as well. The proponents of the Billings Ovulation Method, for example, call it “as safe as the pill but natural.” (According to Contraceptive Technology, the perfect-use failure rates of this method and the pill are 3 and 0.3 percent, respectively.) They ask women to check their cervical mucus in order to find their peak fertility day each month—defined as the last day of slippery cervical mucus. Once a woman has identified her peak, she should abstain from sex for the next four days.

Of course, the peak can only be identified after it passes and the cervical mucus is no longer slippery, so there are many days during which this method’s experts advise women to abstain. First, they recommend not having intercourse during heavy menstrual bleeding because the blood can mask the cervical mucus. They then tell women to observe their mucus every day, and give them a chart to record its properties. Whenever women notice changes, the Billings proponents say, they must wait to have sex. If they have slippery mucus again the next day, they should keep abstaining until the day it stops, and then wait four more days. Moreover, Billings Method endorsers say women should only have sex every other day, even during their safe times, so that they do not confuse semen that has remained in the vagina with cervical fluid and mess up their monitoring.

The other major change around ovulation is in something called basal body temperature (BBT) or the temperature of the body at rest. It is lower early in the cycle, rises right around ovulation, and stays high for the rest of the cycle. A woman can understand her typical cycle and know when ovulation has passed by taking her BBT every morning before she gets out of bed using a very accurate thermometer. The temperature can be taken orally, vaginally, or rectally but should be done the same way and at the same time every morning. She then plots it on a graph and looks for an increase of 0.4 degrees or more. Once a woman notices that her temperature has gone up and stayed up by this amount for more than three days, she can consider it safe to have sex again.

Again, this method does not predict ovulation so much as it tells a woman after the fact that she has ovulated. For this reason, experts in these methods often tell women to look at cervical mucus and BBT together—the mucus tells them when their fertility window has started, and the BBT tells them when it has ended.

The Latest Technology

There are many programs that have been designed to help women keep track of and understand the changes in their cervical mucus and BBT. Most of them were originally developed to help women get pregnant—for those who want to conceive, hitting that six-day window can seem like a daunting task. Now, however, there are fertility apps designed specifically for contraceptive purposes as well.

The newest app picking up steam in the media is Natural Cycles, which costs about $70 per year, allows a woman to record the start and end of her menstrual bleeding as well as any spotting. She then takes and records her BBT each morning. She can also use ovulation test strips, which check urine for spiking luteinizing hormone around ovulation. They are optional—Natural Cycles doesn’t appear to include them in the price—but if women enter the data into the app, they can more accurately determine safe or unsafe days. Finally the woman, can (but does not have to) record dates of intercourse, perhaps for her own records.

Raoul Scherwitzl, CEO and co-founder of Natural Cycles, recently told the Huffington Post that the app does all the hard work for women:

The problem that usually comes with [fertility charting] is that when women look at the charts, the data is usually fluctuating with data points going up and down. It can be very hard to look by eye and make objective decisions on whether she’s fertile that day or not. …  We developed an algorithm that analyzes the data so a woman doesn’t need to learn about “What does it mean if [temperatures] go up and down?” She just needs to measure, then we tell her when she is safe or at risk.

The app labels days as red for unsafe or green for safe. Scherwitzl believes it can be 99 percent effective in preventing pregnancy but, according to the Huffington Post, the study supporting this is still under review. Again, though, it is important to remember that BBT only provides part of the picture. It—and the apps that track it—can only be used to suggest when ovulation has already occurred. As mentioned earlier, sperm can live up to five days and, in fact, pregnancy is most likely if the sperm are already in the reproductive tract “waiting” for the egg to be released. So after-the-fact confirmation might not be good enough in determining which days are the safest.

Efficacy and Alternatives

The efficacy rates of FAB methods vary widely; like all other methods, they depend on how well couples use them. According to Contraceptive Technology, those who used FAB methods correctly and consistently saw failure rates between 0.4 and 5 percent. Under typical use, however, the failure rates are between 12 and 24 percent depending on the specific FAB method.

These perfect and typical use failure rates are only slightly higher to those found with other contraceptives. For example, condoms have a “perfect use” failure rate of 2 percent. This means that when used the right way every time, they are 98 percent effective. In typical conditions, though, they fail up to 18 percent of the time, because couples use them incorrectly or forget to use them at all during intercourse. Meanwhile, the pill has a 0.3 percent failure rate if used perfectly, but a 9 percent failure rate under typical conditions.

The fact that the numbers don’t differ immensely means FAB methods can work. But the key to contraceptive efficacy is always consistent and correct use. With FAB, this would mean keeping track of cycles, cervical mucus, and/or BBT, and then never having unprotected sex during potentially unsafe days. While it certainly can be done, it takes a true commitment, a good understanding of reproductive health and one’s own body, and some daily effort.

The Pope is not wrong that Catholic women can use natural family planning methods to space their children and prevent being like “rabbits.” Still, it is unfortunate that this is the only option the Catholic Church allows, as many modern methods of contraception are more reliable and require far less effort. The IUD, for example, has a failure rate of under 1 percent; once it’s inserted, a woman does not have to do anything for up to ten years to reap its contraceptive benefits. Moreover, women in the parts of the world that inspired the Pope’s comment (he was talking about a Filipino woman he met) often do not have access to the kinds of apps and algorithms that do all the work. Like everyone else, Catholic women around the globe should have access to all methods of contraception and should use FAB methods only if that’s what they really want.

Commentary Contraception

Fancy Birth Control Technology Can’t Solve Everything

Chanel Dubofsky

Apps to track contraceptive use are plentiful, often free or cheap, user-friendly, and undoubtedly helpful to some individuals. But that doesn’t mean that perfect birth control use is a forgone conclusion for everyone.

Lest you think Apple didn’t have enough of a foothold in our lives—often dominating how we communicate, entertain ourselves, and find our way around—it’s now getting involved with reproductive health. Last month, the creators of My Cycles, a free app that includes a birth-control use tracker, announced they would be integrating their program into HealthKit, which has been included with all iPhone software updates since mid-2014. My Cycles also includes an Apple Watch-compatible version. In practice, this means that nearly everyone with an iPhone can access their “symptoms, medications, mood, and more,” as My Cycles’ page in the app store puts it, with the tap of a thumb.

Of course, this isn’t the first example of technology companies using apps to “improve” people’s contraceptive use. In addition to My Cycles, there are approximately eleventy billion other birth control apps available (many of them, naturally, illustrated with pink flowers). You can download programs that will remind you to take your pill or remove your NuvaRing, assist you in locating the nearest condom for sale, and more. MyPill, for example, provides a visual model of a birth control pill pack, a pill disappearing along with your pill cycle (the way it does in your physical pack). The daily alarm will snooze until you mark that you’ve taken the pill—so no absentmindedly turning it off and forgetting to take it. The app also keeps track of symptoms, refills, and doctor’s appointments. NaturalCycles, meanwhile, utilizes an algorithm to monitor the body for signs of fertility based on basal temperature. Multiple platforms are getting in on it too: Lady Pill Reminder is a Google app that asks you to enter the type of pill you use and when, and the app will notify you when it’s time to take it.

So these apps are plentiful, often free or cheap, user-friendly, and undoubtedly helpful to some individuals. But that doesn’t mean that perfect birth control use is a forgone conclusion for everyone. For starters, not every birth control user owns a smartphone, can afford one, or knows how to use one. Some apps do cost money, and while $2.99 might seem like a paltry amount, it can be the difference between being able to travel to work on the train or not. (If you live in New York City, for example, the cost of subway fare for a one-way ride is $2.75.)

Furthermore, they may not be all that effective: It might seem like a simple matter of uploading information, but the reality is that people with vaginas are often not socialized to be deeply in touch with our bodies and their inconsistencies. Irregular periods, for example, can be caused by many things, such as stress, travel, or changes in weight, none of which can be resolved by setting an alarm on your phone. The apps assume that you’ll keep track of these symptoms—many include a space specifically to record them—but they don’t tell you when to call the doctor, other than to refill your pack. This could potentially lead to users failing to contact their physicians when necessary; in practice, it could also just mean that users’ lives aren’t getting any simpler with the aid of such apps. And of course, if you can’t afford to refill your birth control or see your doctor, these apps are moot.  

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They also put the onus of those who use contraceptives to bend over backwards to make sure they’re using them properly—reproducing a narrative that is counterproductively shameful. People who use birth control are often derided when it fails, even by other birth control users. It’s easy to preach if you have never had a birth control failure, even though statistically, you are due for at least one over the course of your reproductive life. When birth control is used “perfectly,” (correctly and consistently), the rates of failure are low, especially for the IUD and implants. But, not surprisingly, when fallible humans are in charge of remembering to get shots, take pills, use barrier methods, and insert devices, failure rates are higher.

These apps make it easier for folks to ignore the complexities of both bodies and birth control, and to shame birth control users for being imperfect humans and consumers. After all, if you can access an app that will remind you, it must be really easy to follow through, right? You have no excuse to mess up. But if you do—and you might, with or without the app—this narrative suggests that perhaps it’s useless to even try, given that even technology can’t guarantee your 100 percent success rate. This is an echo of the frequent watchword of abstinence-only education, “If you don’t want to get pregnant, don’t have sex.” It’s a kind of shame that denies the control that readily available contraception gives individuals: the choice to have sex without submitting to pregnancy, and the dignity to weigh the risks associated with doing so, including the risk of birth control failure.

So while they might certainly helpful to some, in terms of fixing the problem of birth control accessibility, apps are not an equalizer. Apps won’t solve the socioeconomic issues of obtaining birth control or the stigma that surrounds the use of it. Nor will they address the misogynist anti-choice movement’s frequent attempts to block it, which would make it even harder to obtain.

What’s the solution, then? Well, here’s what it’s not: creating policies that prevent folks from having access to free and safe birth control, including emergency contraception, and abortion. Nor is it using innovations in technology as an excuse to not take further action. The solution lies in a push for health care and education, perhaps even spearheaded by tech companies. (The existence of these apps doesn’t negate the fact that education and health care is desperately needed.) Such a strategy would take into account class, race, gender, and sexuality, wouldn’t rely on shaming as a tactic, and would extend to people using non-oral contraceptives as well, taking into account any possible complications.

Apps can be great—but energy also needs to be paid toward enacting policies that will encompass contraception users’ variety of experiences. Downloading an app is not a solution for a larger, innately unequal system.

Commentary Sexual Health

IUDs Might Be Exciting, But There’s More to Sexual Health Than Preventing Pregnancy

Martha Kempner

I worry that in our excitement to promote long-active reversible contraceptives as an effective way of preventing teen pregnancy, members of the public will overlook the importance of sex education and the need for condoms.

Earlier this month, the Centers for Disease Control and Prevention (CDC) released a study that found more people ages 15-to-19 are using long acting reversible contraceptive (LARC) methods than in the past. That rate among young people, however, is still relatively low. The authors of the report join a chorus of public health experts in suggesting that further efforts be taken to increase access to and use of these methods throughout the country.

I worry that in our excitement to promote LARCs as an effective means of preventing teen pregnancy, we will overlook the importance of sex education and the need for condoms—both as an alternative, short-term form of contraception and to prevent sexually transmitted infections.

Contraceptive methods that are safe and highly effective are vital for preventing unwanted pregnancies, but there is more to sexual health than that.

The Methods

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IUDs are small, T-shaped devices that are inserted into the uterus by a physician. They prevent pregnancy primarily by interfering with the path of the sperm toward the egg. Two of the IUDs on the market—Mirena and Skyla—release hormones similar to those in some birth control pills, which create a barrier to sperm by thickening the cervical mucus and may also prevent ovulation. The other type of IUD, called ParaGard, releases copper, which is thought to create an environment that is toxic to sperm. ParaGard lasts for ten years, Mirena for five, and Skyla (which is smaller and was introduced with young women in mind) for three, but any of them can be removed sooner if a user wishes to become pregnant or switch methods.

Contraceptive implants, sold under the brand name Nexplanon, are flexible plastic devices about the size of a matchstick that are inserted under the skin on a woman’s upper arm. Nexplanon releases hormones similar to those in birth control pills, which prevent ovulation and thicken cervical mucus. Nexplanon also lasts three years but can be removed earlier.

LARC methods have the highest efficacy rates against pregnancy, in large part because users can “set them and forget them,” so to speak. Unlike the birth control pill, which a woman has to take every day regardless of whether she has sex, or a condom, which couples must use each time they have sex, these methods work with no effort on the part of the user. This means that the typical-use efficacy rate (the one that shows how well the method usually works for a couple during the first year of use) is very similar to the perfect-use efficacy rate (the one that shows how well the method can work if used consistently and correctly).

IUDs have a failure rate of less than 1 percent; implants have a failure rate of 0.05 percent. In other words, out of 100 couples who use these methods as their primary form of birth control, fewer than one will experience an unintended pregnancy in the first year of use. In comparison, typical use rates for the pill suggest that nine couples out of 100 will experience an unintended pregnancy that first year.

Though IUDs were once thought to be safe only for older women or women who had already had children, research in the past decade has found that they are safe for women of all ages, including adolescents. Implants have also been found to be safe for women of all ages.

The Excitement

Given the safety and efficacy of these devices, it’s easy to see why so many experts feel that LARCs may help prevent teen pregnancy in the United States. After all, if a 16-year-old gets an IUD, there’s almost a guarantee that she won’t get pregnant until she’s 19 at the least.

As Rewire has reported, both the American Congress of Obstetricians and Gynecologists (ACOG) and the American Pediatric Association (APA) have suggested that LARC methods should be a first choice for young women.

ACOG writes:

When choosing contraceptive methods, adolescents should be encouraged to consider LARC methods. Intrauterine devices and the contraceptive implant are the best reversible methods for preventing unintended pregnancy, rapid repeat pregnancy, and abortion in young women.

The APA recommendations are similar:

Pediatricians should be able to educate adolescent patients about LARC methods including progestin implants and IUDs. Given the efficacy, safety, and ease of use, LARC methods should be considered first-line contraceptive choices for adolescents. Some pediatricians will choose to acquire the skills to provide these methods to adolescents. Those who do not should identify health care providers in their communities to whom patients can be referred.

And, this month’s CDC report will likely add to that excitement. The report looked at IUD and implant use among 15-to-19-year-old women who receive health care through Title X clinics. The Title X program provides family planning and related preventive health services for low-income individuals; it serves approximately one million teens nationwide each year.

The report found that among teens who sought contraceptive services at Title X sites, use of LARCs increased from less than 1 percent in 2005 to more than 7 percent in 2013. In 2013, roughly 3 percent of teens who sought contraceptive services used an IUD and 4 percent an implant. Teens older than 18 were more likely than 15-to-17-year-olds to use these methods.

The study also found that the use of LARCs varied widely across states. In Mississippi, for example, less than 1 percent of women ages 15-to-19 used LARCs, but in Colorado that percentage was up to over 28 percent. This finding is not surprising, as Colorado has implemented an initiative designed to improve LARC use among Title X clients.

The authors of the CDC study suggest that more programs like this are needed:

Given the estimated 4.4 million sexually experienced female teens in the United States, and the high effectiveness, safety and ease of using LARC, continued efforts are needed to increase access and availability of these methods for teens.

This month, the CDC also released a Vital Signs document about the key role that the government, health-care providers, and parents can take in helping teens prevent pregnancy. The document points out that about 43 percent of teens ages 15-to-19 have had sex and that four out of five used birth control the last time they had sex—but only 5 percent used “the most effective methods.” (This differs from the CDC study mentioned earlier because that study was limited to teens who sought contraceptive services through Title X providers.) The CDC suggests adults encourage teens to be abstinent, but also encourage the use of LARC methods when they become sexually active. It also suggests the government can help by funding programs, such as Colorado’s, to make such methods affordable and accessible.

The Concerns

While this push toward LARCs is indeed exciting, many public health experts and sexuality educators, myself included, worry that in our rush to promote them we will forget to discuss condoms—or worse, suggest that condoms are not good at preventing pregnancy. We have seen the manufacturers of other birth control methods, such as emergency contraception, throw condoms under the bus by suggesting they break easily. Similarly, the infographics accompanying the Vital Signs document depict the efficacy of various methods—LARC methods are at one end, with few pregnancies, and condoms are at the other, with many.

Though the information is not inaccurate, it does not contain the nuance needed to remind young people that condoms can work very well to prevent pregnancy but have a low typical use efficacy rate because people often make mistakes using condoms: Most notably, they don’t use one every time.

We know that young people often use condoms as their first method of birth control and that those who use them the first time are more likely to do so going forward. We also know that many people rely on condoms when they are in between relationships or in between other methods. This is encouraging for individual and public health reasons, and emphasizing condom failure runs counter to the goal.

And perhaps most importantly, condoms are the only birth control method that provide protection from STIs, for which we know adolescents are at high risk. Adults concerned about teens’ health need to stress dual use for young people: “Even if you or your girlfriend has a LARC, you should still be using condoms.” This will not only protect them from STIs now; it will help ensure their future fertility, as untreated STIs can compromise the ability to become pregnant later in life.

Deborah Arrindell of the American Sexual Health Association (ASHA) explained to Rewire:

LARC are a fantastic addition to the pregnancy prevention [resources]. But unless we are very intentional about promoting dual use of condoms and LARC, we leave young people at risk for HIV and other STIs. In fact, what young women do to prevent pregnancy now, may leave them exposed to complications from STIs that may prevent pregnancy when they want it. Maintaining good sexual health can be challenging, and we need to do everything we can to promote comprehensive messages.

As a sexuality educator, I must also say that I fear LARCs will be seen as a substitute for teaching young people about sex. Sexuality education is already controversial and undervalued. Even educators, advocates, and elected officials who support contraceptive-inclusive sexuality education often sell it primarily as a way to prevent teen pregnancy, because that is more politically expedient than arguing for knowledge for the sake of knowledge. But programs that start and stop with pregnancy prevention—or even STI prevention—don’t help teens understand the characteristics of healthy interactions, examine their own values around sexuality, and think critically about issues such as consent, gender roles, and sexual orientation. 

As Debra Hauser, president of Advocates for Youth, told Rewire:

There are no magic bullets. Young people who wish to use LARC should have confidential, low or no cost access. But LARC will not help reduce sexual assault or young people’s risk for STDs. Nor will LARC, in and of itself, promote healthy relationships. Enthusiasm for the effectiveness of LARC and its ability to prevent unplanned pregnancy should not usurp the importance of helping young people acquire the information and skills they need to develop agency and take personal responsibility for their sexual health and well-being.

Knowledge for the sake of knowledge is important if we want young people to grow up sexually healthy—to understand how their bodies work, have the skills they need to create and sustain good relationships, and make responsible decision about pregnancy and disease prevention. LARC methods can prevent pregnancy, but they can’t do anything else.

We can and should be enthusiastic about LARCs for teenagers. They are safe and highly effective and can help our young people prevent pregnancy in their teen years and beyond. But as we promote these methods and increase access to them, we have to remember to look at the whole picture of sexual health and make sure we do not sell our young people short.


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