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Myth Busters: Fertility Awareness Edition

We've all heard the stories about how guessing when you're fertile is a terrible idea because it's too unpredictable. If you want to protect yourself from an unwanted pregnancy you should either abstain or use a "real" method like the pill or an IUD. FALSE. There is an extremely effective natural method for preventing pregnancy, but it requires commitment. But not much more commitment than committing to take a pill every day.

So let's bust some myths about a very effective contraceptive, Fertility Awareness Method A.K.A. FAM

Myth 1: You can get pregnant at any time.


You only ovulate (release an egg) once per cycle. You may release more than one egg at a time (hey twins!) but you only ovulate once. An egg is only able to be fertilized for about 24 hours. Sperm can survive in a woman for up to 5 days. So basically pregnancy can occur from 5 days before ovulation, up until one day after. These are considered your fertile days. Physiology tells us that it is nearly impossible to get pregnant outside of this 6 day window.

Myth 2: The rhythm method is pretty ineffective.


The rhythm method is about 76-88% effective depending on the source you check. 76% effectiveness is extremely low when you consider we have options like the pill that are nearly 100% effective. The reason this method is so ineffective is because it relies on an average of your previous cycles to make a guess as to when that fertile window is. So if your cycle is typically 28 days on the dot, the rhythm method assumes you always ovulate on day 14. This method works as long as your cycles are extremely regular and as long as you don't have any extreme stress. (Let's be real...stress is a part of life) Stressful situations can cause ovulation to be delayed...even in women who are usually extremely regular. This is where we have our biggest problem.

Imagine you have a textbook 28 day cycle. Your lost your job and have no idea how you're going to pay your bills. STRESS shows its ugly face. This could cause you to ovulate later. Normally your fertile window would end shortly after day 14, but due to stress you ovulated later and were fertile until day 20. This means you could very well get pregnant if you were relying on the rhythm method. This is the rhythm method's biggest fault.

Myth 3: Fertility Awareness Method is the same as the rhythm method.


Unfortunately lots of well educated health care professionals use the terms FAM and rhythm method interchangeably, even though they are completely different. The rhythm method determines when you likely ovulated in the past, and guesses that you'll probably ovulate around the same time in the future. As we already noted that works, until you have a month that is atypical or if you're always irregular. Fertility Awareness Method (FAM) works by telling you exactly when you've ovulated. Without guesswork.


Well short explanation is that before ovulation every woman's temperature is relatively low. After ovulation your temperature goes up. So, if you take your temperature every morning you can take note of that shift and know when you've ovulated. Without question. Which means a few days after ovulation you know for a fact that it is physiologically impossible to get pregnant until your next cycle. This means even if your cycle is irregular, you will still know exactly when you've ovulated by when that temperature shift occurs. FAM is extremely effective when done correctly. 99.6% effective to be exact (which is just as effective as the copper IUD).

Myth 4: My period app tells me when I'm fertile, so I don't need to take temps.


Any app that tells you your fertile days without using your waking temperatures is essentially a fancy version of the rhythm method. It guesses when you'll ovulate based on the length of your past cycles. But we know that's only reliable if your cycle is exactly the same every month. And even if yours is usually the same....what happens when it's not?

Myth 5: Fertility Awareness Method is hard work


FAM requires you to take your temperature every single morning. In the past it has required charting and checking your cervical fluid. There are specific rules about which days are safe days and which days are not. There are courses and instructors who teach the method and the rules. Up until now all FAM apps have been charting apps that essentially plot out a chart of your cycle instead of you doing it by hand. However, it was still up to you to interpret the chart based on the FAM rules. For many people this is too much work. And I understand that. Even I was committed to using FAM as a natural method, and found myself cheating on occasion. I ended up with an IUD for a brief period of time, because I was too lazy to read my charts.

Sounds good in theory, but kind of confusing. Does this chart give you a big old feeling of "NOPE"?

But there's exciting news! A new app was released called Natural Cycles. THIS APP IS AMAZING. I was so excited when I discovered it, and I think it can be the tool that makes FAM more appealing. Natural Cycles allows you to enter your temperature and a few other optional pieces of data. It then takes that current information, interprets the FAM rules, and updates you daily to let you know whether or not you are fertile on that day. It removes the bulk of human error from the equation. Game. Changer.

Same Science. Much less confusing platform

Myth 6: You must be committed to the method for it to work


FAM only works if you do it correctly, every day. It's not a set it and forget it method like the IUD or implant. BUT it is a side effect free method that is extremely effective. The old school method of charting by hand and memorizing the rules of FAM it is very effective, but you must follow the rules to determine when your safe days are. Natural Cycles removes the guesswork and memorization. All you do is take your temp every morning, enter it, and the algorithm does the rest. It's just as easy as taking a pill every day. No more finger crossing and hoping you got the rules right.

Natural Cycles uses "green days" as your safe or infertile days and "red days" as your unsafe or fertile days. Fertile days require your absolute commitment to using protection on those days. Having sex during your red days is always a risk. So, protection is key! The app also gives you the option to take ovulation tests. The app will tell you which days to take them. The extra data will give the algorithm the information necessary to allow you even more green days.

Pretty cool right?





You can officially take your temps every day, and pee on some strips a few days a month, and be protected by a method that is over 99% effective.

Natural Cycles has been approved by the European Union as an official method of birth control. I'm so excited to share this with women who want to ditch the hormones, but still want the effectiveness. Lumos receives nothing from this company or app. I'm just genuinely excited about it. It can even be used to know exactly when you're going to start your period. Even if you're extremely irregular. But that's another blog for another day.

What do you need to start?

Check The Natural Cycles website here. The app if free, but it is a subscription service.

You'll need a basal thermometer. Natural Cycles will ship a free one to you if you opt for a year long subscription. You can also get your own through Amazon here

Still not convinced?

The book Taking Charge of Your Fertility discusses the science in great detail and covers all of the rules for utilizing this method by hand (aka no subscription required) here

A little bit of research here

And a nice NPR piece on Natural Cycles here

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