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Illustrations by Emma Günther

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Clue Birth Control is not the rhythm method

Clue Birth Control is a new, digital fertility awareness based-method of contraception

Top things to know: 

  • Clue Birth Control is not the rhythm method

  • Clue Birth Control is a fertility awareness-based birth control that is evidence based, backed by a clinical trial, and FDA cleared

  • It is hormone free and based on your period start dates

  • Clue Birth Control is 92% effective at preventing pregnancy when used typically and 97% effective when used perfectly

  • Clue Birth Control is for people who are 18-45 years old with cycles that are 20-40 days long and vary by 9 days or less over the last 12 cycles

  • To use Clue Birth Control, enter your period start dates and check the app each time you  have sex

Introducing Clue Birth Control! It’s an FDA-cleared, digital contraceptive that is easy to use to prevent pregnancy. All you need to do is complete our Eligibility Checklist and enter your period start dates to receive predictions for high and low risk days of pregnancy. Tested in a clinical trial, Clue Birth Control is 92% effective at preventing pregnancy when used typically and 97% effective at preventing pregnancy when used perfectly (1). 

Clue Birth Control is non-hormonal and has no side effects, which makes it a non-hormonal form of birth control called a fertility awareness-based method. Let us explain. 

Prevent pregnancy by tracking your cycle with Clue Birth Control

  • Download the Clue app on the App Store
  • Download the Clue app on the Play Store
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Is Clue Birth Control the same as the rhythm method?

While Clue Birth Control is a fertility awareness-based method, it is not the rhythm method. 

“Fertility awareness-based method” is a term used to describe a broad category of birth control that includes many different types of methods like the rhythm method, which is based on cycle length, the TwoDay Method which is based on changes in cervical fluid, and the Symptothermal Method, which uses information about basal body temperature and cervical fluid. For many fertility awareness-based methods there is a lack of high quality research on their effectiveness, meaning that we don’t actually know how effective they are with perfect use (2, 3). These methods require following specific guidelines, so they can be particularly sensitive to incorrect and inconsistent use (4). Many people may only follow the guidelines loosely, which decreases the efficacy (8). Importantly, fertility awareness-based methods are not a "set it and forget it" method of birth control like some long-acting contraceptives because they require active participation and consistently correct usage from the person who uses them (2).

As far as birth control goes, Clue Birth Control is considered a fertility awareness-based method because it is a non-hormonal form of birth control that uses data about your menstrual cycle to identify which days of your cycle you are likely to be fertile. Clue Birth Control makes predictions based on your personalized unique menstrual patterns and personalizes its predictions to you. These predictions are based on the period start dates you enter each cycle. 

If you’d like to read more about the effectiveness of other fertility awareness-based methods, you can read this clinical update for more information about how they are studied. Clue Birth Control is available in the USA from 2022, so it’s not in this review yet, but you can read the research to support the effectiveness of Clue Birth Control here.  

What are the benefits of fertility awareness-based methods?

Fertility awareness-based methods, or FABMs, are low cost, available at any time, and don’t require a prescription (5). They are also hormone-free, which means there are none of the side effects you might expect from hormonal contraception. Many people like fertility awareness-based methods because they are not a medication or physical device that needs to be inserted by a healthcare provider (6). You can start or stop them any time you want, putting you in control of your contraception (5). 

Some research suggests fertility awareness-based methods can improve your sex life (7). Some couples think that using this type of birth control improves their relationship by improving their ability to talk about sexuality (7). Most people can benefit from learning how their body works in regards to fertility—up to 95% of women using fertility awareness-based methods report understanding their body better after using them (7, 8).  

What are the risks of fertility awareness-based methods?

An important thing to know about Clue Birth Control and most other types of contraceptives besides condoms is that they don’t protect you from sexually transmitted infections (STIs) like chlamydia, genital warts, gonorrhea, herpes, trichomoniasis “trich”, syphilis, trichomoniasis, and HIV or AIDS. The United States Preventive Services Taskforce (USPSTF) recommends yearly screening for some STIs if you're sexually active and under 25, or over 25 and have other risk factors like a new partner, multiple partners, or a partner with an STI (9). Talk to your healthcare provider about your STI screening needs before starting a new method of birth control.  

For Clue Birth Control to be effective, you have to accurately enter your period start dates each cycle and check the app each day. On high risk days, use a barrier method such as a condom every time you have sex that may result in pregnancy.

Image of the phases of the menstrual cycle

Is Clue Birth Control effective?

Clue Birth Control is 97% effective at preventing pregnancy when used perfectly or as directed and 92% effective when used typically (1). 

Research to support the effectiveness of Clue Birth Control was conducted by the Institute for Reproductive Health (IRH) at Georgetown University in Washington, D.C. These experienced researchers conducted an ethics board approved rigorous clinical trial to test the effectiveness of the algorithm behind Clue Birth Control used to predict high and low risk days of pregnancy. 

In addition to that, after meticulous review, the United States Food and Drug Administration (FDA) cleared Clue Birth Control as a software application that can be used as a contraceptive to prevent pregnancy. Clue Birth Control received this certification after submitting extensive documentation about its efficacy, the research behind it, and the processes our team has in place to make sure the app is implemented safely and accurately. 

In order to safely use Clue Birth Control, you must meet the eligibility criteria. You should be between 18 and 45 years old and your cycles should be longer than 20 days, but shorter than 40 days. The difference between your shortest cycle and your longest cycle over your past 12 cycles should be 9 days or less. Clue Birth Control is not the right birth control option for you if your cycles haven’t returned to predictable cycles after being pregnant or using hormonal birth control. You can use Clue Birth Control while breastfeeding/chest feeding, as long as your cycles fit the eligibility criteria.

Clue Birth Control is an innovation in birth control

Clue Birth Control is a new form of digital birth control that uses your period start dates to predict your high and low risk days for pregnancy. It’s science-based and FDA cleared as an effective method of preventing pregnancy. Using Clue Birth Control means you’re in charge of your contraception and you won’t experience any of the side effects of hormonal birth control.

Clue Birth Control will be launched in the USA in 2022. We are excited to bring Clue Birth Control to other countries soon. This will take a little more time, but we’re on it.

an illustration of the Clue flower
an illustration of the Clue flower

Live in sync with your cycle and download the Clue app today.

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