Natural birth control: does it work?

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Rachel Honeyman 

Mike Bohl, MD, MPH, ALM - Contributor Avatar

Written by Rachel Honeyman 

last updated: Dec 22, 2020

6 min read

Women have been finding ways of preventing pregnancy throughout history. We've come a long way since the days of women using acacia leaves and honey as a barrier against semen entering the vagina (O'Reilly, 2010). 

One of the most effective methods of contraception is hormonal birth control, which works by giving the body hormones to prevent pregnancy (examples include the pill, vaginal ring, injections, implants, and some intrauterine devices). Many women, though, prefer not to use hormonal birth control methods for a number of reasons and opt for natural birth control methods instead. 

This article will cover the most common natural contraception options used today. We'll also answer the most important question of all: Does natural birth control work? 

Birth control

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What is natural birth control? 

Natural birth control is a broad term that can refer to several methods of timing intercourse to avoid insemination while a woman is fertile. The fertile window is generally five days leading up to ovulation (since sperm can live in the body for up to five days), plus the day of ovulation itself, adding up to six fertile days in total (Wilcox, 2000). 

The most common category of natural birth control is often referred to as fertility awareness methods (FAM) or natural family planning methods (NFP). These methods are based on learning the hormonal rhythms of the body by tracking or measuring the fertile time in different ways. The end goal is to avoid sex during those fertile days, with most methods extending that window a few days in either direction to be on the safe side. 

Some FAM methods involve tracking on a calendar, while others involve taking your temperature, testing your cervical mucus (discharge from your cervix), or measuring hormones in your urine (Peragallo Urrutia, 2018). 

Other forms of natural birth control include the withdrawal (or pull-out) method and breastfeeding. These work differently than the FAM methods, as we'll discuss shortly, but they have the same goal of avoiding pregnancy without the use of external hormones or barriers. 

Does natural birth control work? 

It depends on the method. 

With fertility awareness methods, it's hard to say for sure how effective they are because there's almost no high-quality research available on these methods. The studies we have show that with perfect use, FAMs are about on-par with condoms, the gold standard barrier method (95–98% effective). Perfect use means exactly that—using the chosen method perfectly throughout your cycle.

We're all human, though, so typical use effectiveness rates might be more telling. Typical use is how the average person uses a given method, meaning they might sometimes forget or not use it exactly the same way every time. With typical use, fertility awareness methods are estimated to be about 85% effective (Peragallo Urrutia, 2018). To compare, hormonal birth control options range from 91% effective with typical use to 99.95% effective at preventing pregnancy with perfect use (Trussel, 2011). 

Other types of natural birth control have varying rates of effectiveness. Using breastfeeding as birth control is 98% effective—when used perfectly (Trussel, 2011). The pull-out method, though, is only about 82% effective with typical use (Jones, 2014). We'll now take a closer look at these approaches.

Fertility awareness methods (FAM) 

There are at least a dozen different types of FAMs that people use for birth control. We have limited research for most of these methods, but we'll go over some of the most common ones. All of these methods follow the same principle that by accurately tracking where you are in your cycle, you can avoid unprotected sex during the week or so when your body is capable of getting pregnant (your fertile days). 

Calendar methods

The Standard Days Method is the most common calendar method, where you keep track of the days of your cycle using a calendar. Calendar methods are also sometimes referred to as the "rhythm method." With the Standard Days Method, you'd avoid sex on days 8–19 of your cycle, the window where your fertile days most likely fall. To use this method, your average cycle needs to be 26–32 days long. 

With perfect use, the Standard Days method is 95% effective, but with typical use, it's about 86–89% effective (Peragallo Urrutia, 2018). 

Mucus methods

These methods involve tracking your cycle by monitoring cervical mucus changes. There are two main methods in this category: 

  • TwoDay method: This method assumes that any day a woman has vaginal secretions or the day following is a potentially fertile day, so vaginal sex should be avoided. It's called the TwoDay method because you'll check for secretions twice a day. 

  • Billings ovulation method: This method is similar to the TwoDay method but involves paying attention to the color and thickness of secretions from the cervix to determine which days you need to avoid sexual intercourse. 

The benefit of both of these methods is they do not rely on having a reliably consistent menstrual cycle, so even if your period is irregular, you can use these methods. 

In terms of effectiveness, the TwoDay method is about 96% effective with perfect use and 86% effective with typical use. The Billings ovulation method is 97–99% effective with perfect use, but with typical use, it's anywhere from 66% to 89% effective (Peragallo Urrutia, 2018). 

Symptothermal method 

"Symptothermal" is just a fancy way of saying this method combines your symptoms—namely, your vaginal secretions—with your temperature to determine your fertile window. The body's baseline temperature (called the basal body temperature) tends to be slightly higher than normal when you're ovulating—we're talking about half a degree higher than usual. 

Using basal body temperature alone (called natural cycles) is not reliable since it only tells you when you're probably actively ovulating, while the fertile window generally begins about five days before ovulation. 

When used in combination with mucus methods, though, it might be a potential natural birth control method. The symptothermal method is about 98% effective when used perfectly, but it's only about 80–87% effective with typical use (Sung, 2020). 

Urinary hormone method

With the urinary hormone method, in addition to tracking mucus changes, you'll use a device to measure the levels of estrogen and luteinizing hormone (LH) in the urine. A few days before ovulation, the body's estrogen levels increase, which causes a surge of LH. A day or so after the LH surge, an egg is produced—that's ovulation in a nutshell (Holesh, 2020). 

So, measuring your estrogen and LH levels gives you a pretty good idea of when you'll be ovulating. One of the most commonly used devices is called the Marquette Method. One study showed this method to be 99.4% effective with perfect use and 89.4% effective with typical use (Fehring, 2008). 

Other natural contraception methods

As you can see, most fertility based-awareness methods work well when used perfectly, but those numbers drop off pretty dramatically with typical use. There are a couple of other natural birth control methods to consider, though. 

Withdrawal (pull-out) method

The withdrawal method is where the male partner withdraws before letting any ejaculate get into the vagina. This is not a very reliable form of birth control, but many women rely on this method, so it's worth discussing. 

With perfect and exclusive use of the withdrawal method, it's only about 82% effective (Kost, 2008). This is likely because there can be some sperm in pre-ejaculatory fluid, so unless the timing is perfect (which is very difficult to predict), there's a good chance some sperm may get released into the vagina even before ejaculation (Killick, 2010). One study showed, however, that a large percentage of women who use the pull-out method do so while using a back-up method, such as the pill, condoms, or spermicide. When combined with another method, unwanted pregnancies go down (Jones, 2014). 

Breastfeeding (lactational amenorrhea)

Breastfeeding is one of the oldest forms of birth control after giving birth. This is related to the changes in the hormones that happen when breastfeeding. Another name for this method is the lactational amenorrhea method (LAM) because what happens with breastfeeding is that it keeps the ovaries from ovulating, which prevents the woman from getting her period (amenorrhea = no menstruation).

This method can be more than 98% effective at preventing pregnancy for up to six months, but only if two factors are in place (Trussel, 2011): 

  • Breastfeeding must start right away before you get your first period after giving birth. 

  • Breastfeeding has to be done exclusively or nearly exclusively. 

If those things are in place, breastfeeding is an effective method of birth control right after giving birth. If those criteria aren't met, progestin-only birth control pills or intrauterine devices (IUD) are usually recommended for breastfeeding women who want to prevent pregnancy (Phillips, 2015). 

Long-acting contraception

One other method of contraception that's worth mentioning is the category of long-acting reversible contraception (LARC). This includes IUDs and contraceptive implants. While some of these are hormonal, there is a copper IUD available that many women prefer as a non-hormonal method of birth control (Kaneshiro, 2010).

There are also non-reversible options. 

While not always considered a "natural" form of birth control, since it involves a surgical procedure, some people choose this option if they know they will no longer want children and don't want to use hormonal contraceptive methods. In women, tubal ligation (commonly called having your tubes tied) is the procedure for female sterilization. During this procedure, the fallopian tubes are cut, tied, or blocked off so that no sperm (or egg) can get through. Male sterilization is called a vasectomy. 

Benefits and drawbacks of natural birth control

Many women swear by natural birth control methods because: 

  • There are no side effects or safety risks. 

  • They feel more in tune with their reproductive health. 

  • They're affordable. 

These benefits aren't necessarily true of LARCs (surgery is certainly not without its risks or costs!), but most of the other methods we've discussed come with these benefits. 

That's not to say natural birth control methods are for everyone, though. When you combine all fertility awareness-based methods (FABM), one review showed that 24% of women using them experienced an unwanted pregnancy within one year, compared with 0.05–9% across all hormonal contraception options (including birth control pills, IUDs, and implanted devices) (Trussel, 2011). For many women who are serious about preventing pregnancy, the risks of unwanted pregnancy with FABM are simply too high. 

And, of course, any birth control method (natural or hormonal) other than condoms will not protect you against sexually transmitted infections (STIs). 

The contraceptive method you use is a personal decision based on various factors. Your healthcare provider can help you make the right choice for your needs.

DISCLAIMER

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.


How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

December 22, 2020

Written by

Rachel Honeyman

Fact checked by

Mike Bohl, MD, MPH, ALM


About the medical reviewer

Dr. Mike is a licensed physician and a former Director, Medical Content & Education at Ro.