Everyone has their own unique reasons for considering the switch to natural birth control. Hormonal birth control isn’t for everyone, especially considering the potential side effects: depleted sex drive, weight gain, moodiness, and depression to name a few (1).
Fertility awareness-based methods (FABMs) are birth control options that are noninvasive, nonsurgical, and nonhormonal. These methods involve identifying your fertile window within each menstrual cycle so that you can make informed decisions about when and how to have sex.
With perfect use, the Symptothermal Method (which we recommend) is over 99% effective (10). However, there is no such thing as being only 1% pregnant. If getting pregnant is absolutely not an option due to health or personal reasons, your best bet will be to use two different forms of protection, such as condoms plus an additional type of birth control such as an IUD.
Are you thinking of using a natural birth control method? Whether you are looking for a way to get off the pill or trying to find a technique that helps you feel more in sync with your body’s monthly cycles, we suggest asking yourself the following five questions before making the switch.
The Symptothermal Method (STM) of natural birth control can be a great tool for learning more about your body and your fertility. With perfect use, this method has been found to prevent unwanted pregnancies in over 99% of women (10). However, FABMs can not protect you from sexually transmitted infections and diseases.
Relying solely on FABM(s) may not be right for you if:
If either of the above is true for you, you can still use FABM(s) to track your fertility cycles and gain empowering knowledge about how your body works, but you should also use condoms to help protect yourself from STDs.
Note that even condoms are not 100% effective against STDs, especially those that are spread through skin-to-skin contact, such as syphilis and genital herpes (3).
While the birth control method that you use is ultimately your choice, to be effective, FABMs require more cooperation with your partner than other methods such as the pill or an intrauterine device (IUD). You and your partner should be on the same page before switching birth control methods, especially because misusing FABMs can cause your chances of unwanted pregnancy to jump to 13 – 20% (4).
Another thing to consider is whether your partner is on board to abstain from intercourse or use a barrier method during your fertile window. FABMs can only be effective if you can do both of the following:
Again, your birth control methods are your choice, but your partner also deserves to make an informed decision before intercourse. If you’re considering switching to a natural form of birth control, you should first discuss how it can affect your chances of conception. If your partner is unsure about the reliability of FABMs, you can share this post: Are Fertility Awareness Methods Effective for Avoiding Pregnancy?
As we said in the previous section, avoiding sex or using another form of protection during your fertile window is key to the effectiveness of FABMs. During your cycle, your fertile window is the only time you can become pregnant. It’s typically described as being 6 days long — the 5 days before ovulation and the ovulation day itself (5).
If you have unprotected sex during your fertile window, there is an increased likelihood that you will conceive. (In fact, many couples who are trying to conceive use FABMs to help them track ovulation and determine the best times each month to have intercourse.)
One study found that among women using the Symptothermal Method, those who had unprotected sex during the fertile window had pregnancy rates of 7.46%. The pregnancy rates of couples who abstained from sex or used an additional contraception method during the fertile window? 0.43% or 0.59%, respectively (6).
So, think about it realistically. Will you and your partner be able to abstain or use additional protection during your fertile windows? If not, FABMs may not be the best method for you.
The Symptothermal Method involves familiarizing yourself with your basal body temperature (BBT), cervical mucus (CM), and optionally, cervical position. Each of these factors fluctuates in specific ways throughout your menstrual cycle, and it takes time to learn how to interpret these changes.
The only way to avoid unprotected sex during your fertile window is to know with confidence when you are fertile and when you are not. The STM relies on more than one biomarker (typically BBT and cervical mucus) to confirm where you are in your cycle, which is one reason why the method is so effective. Learning how to measure and chart these biomarkers involves a commitment that some couples may not have the time or patience to get right.
If you’re interested in learning more, we recommend checking out Toni Weschler’s book, Taking Charge of Your Fertility. Find additional information and resources about STM for avoiding pregnancy here or sign up for our free educational email series on using the Symptothermal Method.
To use the Symptothermal Method the correct way requires dedication to tracking and recording your BBT and CM every day. Because this method relies on information from multiple sources To identify your fertile window each cycle with confidence, you cannot slack on this and still expect this method to be effective. This is not the only FABM available, but whichever method you choose, be sure to measure at least 2 physical biomarkers, including one that is predictive of ovulation. Only cervical mucus and continuous core body temperature measurements are predictive of ovulation (11, 12).
To get an idea of the time commitment required for STM, here are 2 fertility signs you need to track every day, plus an optional sign:
Basal body temperature (BBT)
BBT is your body’s resting temperature when you wake up each morning; take your temperature every day immediately after you wake up. Your temperature may hit its lowest point right before you ovulate and rise by about 0.5 to 1°F the day after you ovulate (7). After ovulation, your BBT will stay elevated until the start of your next period. (Check out our BBT 101 post for more tips on getting the most accurate BBT readings.)
If you are unable to take your daily BBT readings for any reason, some women may use LH instead of BBT to avoid pregnancy, with caveats. To learn more about the pros and cons of using LH in place of BBT click here.
Cervical mucus (CM)
Your cervical mucus will change in color and consistency throughout the different phases of your cycle. By tracking the changes in CM, you can estimate your body’s fertile period (8). Typically, after your period, CM will be dry or nonexistent. It will become more watery as your body gets closer to ovulation. After ovulation, CM will start to become more dry and sticky in the days leading up to your period. If you’re using STM, you’ll need to check your CM throughout the day and note any changes as the CM makes its way from your cervix to the opening of your vagina.
For more in-depth descriptions of the different types of CM, click here.
Cervical position (Optional)
Not everybody checks their cervical position as a part of the Symptothermal Method, but it can be an added tool to confirm your fertility on a given day. Taking note of your cervical position can be especially important on the days right before and after ovulation (9). It can also help clear up any ambiguities in your BBT and CM.
Your cervical position, texture, and degree of openness will change depending on where you are in your cycle. Interpreting the changes in your cervix involves consistent checking and day-to-day comparisons (click here to learn how to check your cervical position).
It will take a few cycles to learn your personal BBT, CM, and cervical position patterns. You should continue using additional forms of protection while you are still learning the ins and outs of any new natural birth control method and the patterns of your unique body. When used correctly and consistently, FABMs can be an effective way to not only avoid pregnancy but to also get in tune with your body’s fertility cycles.
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