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A Super Long List of Fertility Awareness Based Methods (FABMs)

A Super Long List of Fertility Awareness Based Methods (FABMs) | Starry-Eyed Pragmatist

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This post is periodically updated when I come across new information. 


Fertility Awareness Based Methods (FABMs) use observations recorded, or charted, about your individual fertility signs to determine if you are fertile or infertile each day. On the days the method indicates you are fertile, you either abstain from sex or you use an Intercourse Dependent Birth Control (IDBC), also known as having “protected sex” (such as condoms, etc.), to avoid pregnancy. If you are trying to conceive, then you focus your timing of sex on the days the method indicates you are fertile.

There are lots of different FABMs to help a woman figure out when she is fertile and infertile each cycle. Some have a better efficacy than others, however choosing a method that you will actually follow is way better than badly following another “better” method. Here’s a list of all the FABMs I know about, along with a few things that get commonly get mistaken as FABMs. Also included is the method’s correct/perfect use efficacy stats (effectiveness in avoiding pregnancy), if known. This information is accurate to the best of my knowledge, however please seek out a method instructor for the most accurate and up-to-date information on that FABM.

Simplified Methods

(aka Methods Based on Averages, Calendar Methods, Counting Days Methods)

These methods are primarily based on the statistical likelihood of an average woman being fertile at a given time in her cycle. So, think of it as general information about your fertility rather than specific information about your individual fertility status. The effectiveness is typically lower for these methods.

  • Calendar Rhythm Method (aka Knaus-Ogino Method): 91%
    This is the older forerunner to modern FABMs and was developed in the 1930s. In this method you chart your period days and cycle length, then follow a calculation based on past cycles to figure out when you should be fertile in the current cycle. This method is NOT RECOMMENDED and not considered as an effective, modern FABM.
  • Cycle Beads (aka Standard Days Method): 95%
    This method is for women who regularly have a cycle length between 26-32 days long. In this method you chart the first day of your last period and then the method says that you should consider cycle days 8-19 to be fertile. This method is very simple to use (there’s even an app for it), but not as effective as other FABMs that have you chart individual biomarker (or fertility signs).
  • Dynamic Optimal Timing (DOT) app: 99%
    This method is for women who regularly have a cycle length between 20-40 days long with less than 10 days variation in a given year. In this method you chart the first day of your last period and then the method calculates the days you (as a general woman with a similar cycle length) are statistically likely to be fertile and infertile. This method was developed by Cycle Technologies, the same research group that developed the Standard Days Method. “Dynamic Optimal Timing™ (Dot™) is a patent-pending family planning and birth control method that tells you your risk of pregnancy every day. Although the science and statistics behind Dot are complicated, using it is not. Just enter your period start date into the app each cycle and Dot does the rest. No gadgets, subscriptions, or external hardware needed. All you need is your smartphone, Dot the app, and your period start dates.” The DOT app is free to download and use the fertility algorithm. There is currently an option to upgrade to DOT Pro, which add a few convenience features such as calendar sync, notifying your partner, and changing the apps colors. This method is very simple to use. According to computer models the DOT app is estimated to be 97% effective at preventing pregnancy and they are currently in clinical trials to get an actual use efficacy.
  • Two Day Method: 96.5%
    In this method women chart their period and either the presence or absence of cervical fluid. The method uses that information to determine the statistical likelihood of a general woman being fertile or infertile. There is no need to differentiate between the different types of CF in this method, a woman simply needs to be able to recognize if CF is present or not. This method is fairly simple to use (there’s even an app for it), but not as effective as other FABMs. This method doesn’t strictly belong in this category, because it does involve observing the very important fertility sign of cervical fluid, but it is a very simplified and statistical averaging version of applying CF observations. This method is also listed under Cervical Fluid Only Methods.

Cervical Fluid Only Methods

In these methods women chart their period and moderately to very detailed observations about their cervical fluid (depending on the method). It is highly recommended to work with an instructor to learn and practice CF only methods.

  • Billings Ovulation Method (BOM): 98.9%
    In this method women chart their period and observations about sensations at the opening of the vagina about their cervical fluid (CF). There are no internal checks, no handling or stretching CF, the only time you add a visual observation of CF is when it happens in the normal course of the day. The app NFP Charting uses the Billings notation system. It is highly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method may also likely include some information on Catholic religious teachings concerning sex. You can read more details about this method in the book “Billings Method: Controlling Fertility without Drugs or Devices” by Evelyn Billings.
  • Creighton Method (CrM): 98.7%-99.5%
    In this method women chart their period and very detailed observations about their cervical fluid. The CF observational method and charting system taught with Creighton is similar to that taught with the Justisse Method. It is highly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex. Creighton is similar to the method taught with the Justisse Method, however there is no religious affiliation with the Justisse Method.
  • Family of Americas Foundation Ovulation Method
    In this method women chart their period and very detailed observations about their cervical fluid. It is highly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.
  • Two Day Method: 96.5%
    In this method women chart their period and either the presence or absence of cervical fluid and the method uses that information to determine the statistical likelihood of a general woman being fertile or infertile. There is no need to differentiate between the different types of CF in this method, a woman simply needs to be able to recognize if CF is present or not. This method is fairly simple to use (there’s even an app for it), but not as effective as other FABMs. This method is also listed under Simplified Methods.

Cervical Fluid + Basal Body Temperature Methods

aka Sympto-Thermal Method (STM): 98%-99.6%

In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. Couples are better able to effectively use this method when taught by an instructor, but many have successfully used this method from being self-taught.

  • Sensiplan 99.6%
    This method is very popular with Celsius charters. There are only slight differences from the FAM rules, including rules that simplify chart interpreting for those charting in Celsius. In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. Couples are better able to effectively use this method when taught by an instructor, but many have successfully used this method from being self-taught.
  • INER (Rötzer Method) 99.8%
    (Institute for natural conseption regulation | Institut für Natürliche Empfängnisregelung Prof. Dr. med. Rötzer (INER) e.V. )
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. Couples are better able to effectively use this method when taught by an instructor.
  • Neo Fertility
    In this method women chart their period, detailed cervical fluid observations, and basal body temperature (BBT). The method combines aspects of Creighton, Billings, and Sensiplan. Couples are better able to effectively use this method when taught by an instructor. The method is meant to be used with the app Chart Neo.
  • Natural Family Planning Teachers’ Association (NFPTA)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. Couples are better able to effectively use this method when taught by an instructor, but many have successfully used this method from being self-taught. The online, self-teaching resources are for Celsius charting, but I understand NFPTA instructors are taught to teach the method in Fahrenheit or Celsius.
  • Grace of the Moon
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This method is not affiliated with any religious teachings.
  • Couple to Couple League (CCL)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.
  • Natural Family Planning International (NFPI)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.
  • Natural Family Planning Teachers Association of Ireland (NFPTAI)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.
  • Australian Council of Natural Family Planning (ACNFP)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This method is primarily taught and based in the Australia. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.
  • Natural Fertility NZ (NFNZ)
    In this method women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. This method is primarily taught and based in the New Zealand. This method is not affiliated with any religious teachings.
  • Serena
    In this method, women chart their period, moderately detailed cervical fluid observations, basal body temperature (BBT), and optionally, their cervical position details. Celsius charters are better able to effectively use this method when taught by an instructor. This is an independant non-profit organization recognized by Quebec Health Services in Canada and not affiliated with any religious teachings.
  • Boston Cross Check (BCC)
    This method is typically practiced with Clearblue Fertility Monitor results (measures LH and Estrogen), basal body temperature (BBT), and moderately detailed observations about cervical fluid (CF), however there is a protocol for CF + BBT observations. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method may also include some information on Catholic religious teachings concerning sex. See the listing under Cervical Fluid + Basal Body Temperature + Hormone Monitor Methods for more details about this method.
  • Justisse Healthworks For Women
    (same method taught by Lisa of the Fertility Friday Podcast)
    This method is typically practiced as a CF only method, however Justisse does have an option to add a BBT protocol in C as a cross check. In this method women chart their period and very detailed observations about their cervical fluid (CF). Justisse does have an option to add a BBT protocol in C as a cross check, however Justisse is primarily a CF only method. The CF observational method and charting system taught with Creighton is similar to the method taught with the Justisse Method, however there is no religious affiliation with the Justisse Method. It is highly recommended to work with an instructor to learn this method. Read more about this method in the book “Justisse Method: Fertility Awareness and Body Literacy A User’s Guide” by Geraldine Matus.

Cervical Fluid + Luteinizing Hormone Test Methods

In these methods women chart their period, cervical fluid (CF) and luteinizing hormone tests (also called LH tests, ovulation predictor kits and OPKs) results. It is highly recommended to work with an instructor to learn this method.

Cervical Fluid + Hormone Monitor Methods

aka Sympto-Hormonal Method

In this method women chart their period, Clearblue Fertility Monitor results (measures LH and Estrogen), and moderately detailed observations about cervical fluid (CF). These methods are highly recommended among postpartum women who have not had their return of fertility. It is highly recommended to work with an instructor to learn and practice these methods.

  • Marquette Method: 98%-99%
    In this method women chart their period, Clearblue Fertility Monitor results (measures LH and Estrogen), and moderately detailed observations about cervical fluid (CF). The monitor works by detecting hormone changes in your urine through disposable test sticks. Requires a one-time purchase of the monitor and on-going purchases of the test sticks. There is also additional protocols for CF only or monitor results only with this method. This method comes highly recommended among postpartum women who have not yet had the return of their regular cycle. It is strongly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.

Cervical Fluid + Basal Body Temperature + Hormone Monitor Methods

In these methods women chart their period, Clearblue Fertility Monitor results (measures LH and Estrogen), and moderately detailed observations about cervical fluid (CF), and basal body temperature (BBT). It is highly recommended to work with an instructor to learn and practice these methods.

  • Boston Cross Check (BCC)
    In this method women chart their period, Clearblue Fertility Monitor results (measures LH and Estrogen), moderately detailed observations about cervical fluid (CF), cervical position (CP), and basal body temperature (BBT). You do not have to chart all these signs, but you work with a BCC instructor to determine the right combination of cross checks to chart. The monitor works by detecting hormone changes in your urine through disposable test sticks. Requires a one-time purchase of the monitor and on-going purchases of the test sticks. There are optional protocols with this method to only use two out of those three fertility signs used by the method. The protocol for CF and monitor results (similar to the Marquette Method) for the BCC method comes highly recommended among postpartum women who have not yet had the return of their regular cycle. It is strongly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex.

Hormone Monitor Only Methods

In these methods women chart their period and either Clearblue Fertility Monitor results or the Persona Fertility Monitor results (both are made by the same company and measures LH and Estrogen). Requires a one-time purchase of the monitor and on-going purchases of the test sticks.

  • Persona Fertility Monitor: 94%
    In this method women chart their period and Persona Fertility Monitor results (measures LH and Estrogen). The monitor works by detecting hormone changes in your urine through disposable test sticks. Requires a one-time purchase of the monitor and on-going purchases of the test sticks. This method is NOT the same protocol as the Marquette Method or the Boston Cross Check method. See the listing under Fertility Monitor Methods for more details about this method.
  • Boston Cross Check (BCC)
    This method is typically practiced by women cross checking two or more fertility signs: Clearblue Fertility Monitor results (measures LH and Estrogen), cervical fluid (CF), cervical position (CP), and basal body temperature (BBT), however there is a protocol for monitor only observations. The monitor works by detecting hormone changes in your urine through disposable test sticks. Requires a one-time purchase of the monitor and on-going purchases of the test sticks. It is strongly recommended to work with an instructor to learn this method. This is a Catholic-based Natural Family Planning (NFP) method, so instruction in this method will also likely include some information on Catholic religious teachings concerning sex. See the listing under Cervical Fluid + Basal Body Temperature + Hormone Monitor Methods for more details about this method.

Basal Body Temperature Only Methods

In these methods women chart their period and basal body temperature (BBT). Many fertility monitors use BBT alone as its only fertility sign. BBT only methods are NOT RECOMMENDED for POSTPARTUM women who have not yet had their first period.

  • Lady Comp Fertility Calculator: 99.3%
    This method is for women who regularly have a cycle length between 19-40 days long. In this method women chart their period and use the Lady Comp device to take their basal body temperature (BBT) each morning. The device will then calculate fertile and infertile days. This method is very simple to use. I do NOT RECOMMENDED this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period. See the listing under Fertility Monitor Methods for more information.
  • Daysy Fertility Monitor: 99.3%
    This method is for women who regularly have a cycle length between 19-40 days long. In this method women chart their period and use the Daysy device to take their basal body temperature (BBT) each morning. The device will then calculate fertile and infertile days. There is a smartphone app the device can sync with. This method is very simple to use. I do NOT RECOMMENDED this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period. See the listing under Fertility Monitor Methods for more information.
  • Natural Cycles App: 99.5%
    In this method women chart their period, basal body temperature (BBT), and optionally, LH test results. Then the proprietary app algorithm evaluates if you are fertile and infertile each day. This method is very simple to use. I do NOT RECOMMENDED this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period. See the listing under Fertility Monitor Methods for more information.
  • Natural Family Planning Teachers’ Association (NFPTA)
    This method is typically practiced with CF and BBT, however there is a BBT only protocol. The BBT only protocol is NOT RECOMMENDED for POSTPARTUM women who have not yet had their first period. See the listing under Cervical Fluid + Basal Body Temperature aka Sympto-Thermal Method for more details about this method.
  • OvuSense Fertility Monitor
    OvuSense is a wearable basal body temperature (BBT) thermometer that is “worn” in the vagina at night while you sleep. It also comes with an app to predict fertility based on BBT only. It is marketed towards women TTC (trying to conceive) and it is unclear if the app is useful for birth control purposes (TTA, trying to avoid pregnancy). OvuSense is not officially recommended as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period. See the listing under Fertility Monitor Methods for more information.

Basal Body Temperature + Luteinizing Hormone Test Methods

In these methods women chart their period, basal body temperature (BBT) and luteinizing hormone tests (also called LH tests, ovulation predictor kits and OPKs) results results. BBT + LH test methods are NOT RECOMMENDED for POSTPARTUM women who have not yet had their first period.

Luteinizing Hormone Test Only Methods

NOT AN OFFICIAL FABM

Luteinizing hormone tests (also called LH tests, ovulation predictor kits and OPKs) measure if luteinizing hormone (LH) has reached a certain threshold. A positive LH test result indicates a woman’s body is preparing for ovulation, however it does not confirm that ovulation will definitely happen. There is NO OFFICIAL FABM protocol for only this fertility sign. However, LH tests can be used as a cross check with an official FABM protocol.

Progesterone Hormone Test Only Methods

NOT AN OFFICIAL FABM

Proov tests, also called Progesterone test strips and/or Pregnanediol Glucuronide tests, PDG tests, measure if Pregnanediol Glucuronide (PDG) has reached a certain threshold. PDG tests measures the presence of PDG in urine, which has been shown to directly correlate with the presence progesterone in serum (blood). A positive Proov result indicates that a woman is likely in her luteal phase. Proov tests were developed by MBF Fertility. There is NO OFFICIAL FABM protocol for this fertility sign. However, Proov tests can be used as a cross check with an official FABM protocol.

Electrolyte Only Methods (Saliva Ferning / Cue Method)

NOT AN OFFICIAL FABM

In these methods women use a device or microscope to determine changes in electrolytes of saliva and/or cervical fluid. There is NO OFFICIAL FABM protocol for this fertility sign. These methods are NOT RECOMMENDED as a sole indicator of fertility status for birth control, and especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period.

  • OvaCue Fertility Monitor / OvaCue Mobile Fertility Monitor
    This device is specifically marketed for TTC and not officially licensed for birth control use (TTA, trying to avoid pregnancy). However, some women have attempted to use it for TTA purposes. There is no reliable, studied protocol for using OvaCue to avoid pregnancy. For TTC purposes, it says “proven 98.3% accurate in government-sponsored NIH study.” The monitoring set comes with two sensors: the OvaCue Oral Sensor and the OvaCue Vaginal Sensor. The two OvaCue sensors can be used with either the stand-alone OvaCue device or your smartphone with the OvaGraph app to take a measurement. In this method women chart their period, OvaCue Oral Sensor results (measures saliva electrolytes), and OvaCue Vaginal Sensor results (measures cervical fluid electrolytes). Changes in the electrolytes (sodium and potassium) content are caused my changes in estrogen production, which indicate changes in the fertility cycle. When given sensor readings the stand-alone OvaCue device or the OvaGraph smartphone app then predicts your fertile window. Readings from the OvaCue Oral Sensor should indicate the start of the fertile window and readings from the OvaCue Vaginal Sensor should indicate the close of the fertile window (ie. that ovulation has occurred and you are in your infertile luteal phase). The device is fairly expensive, but it is only a one-time purchase with no additional cost to continue using. OvaCue is not officially recommended as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period. Also, see the listing under Fertility Monitor Methods.
  • Saliva Ovulation Microscope
    In this method women place a saliva sample on glass (as indicated) first thing in the morning upon waking (no eating, drinking beforehand). Then the saliva is allowed to dry. The presence of a ferning pattern of dried saliva under a 60x-100x microscope indicates an increase in electrolytes, which happens with an estrogen surge and indicates increased fertility. Devices for this method are marketed towards the goal of conceptions and are not approved for birth control use. This method is NOT RECOMMENDED as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period.

Fertility Monitor Methods

In these methods women use a device or app to calculate their fertility status based on the observational data measured by the device and/or manually inputted.

  • Lady Comp Fertility Calculator: 99.3%
    This device is from the same people who make the Pearly and Daysy, and uses the same algorithm, but the Lady Comp device is larger than Daysy and Pearly, and marketed separately. In this method women chart their period and use the Lady Comp device to take their basal body temperature (BBT) each morning. The device will then calculate fertile and infertile days. Unlike the Daysy Fertility Monitor, which is made by the same company and uses the same algorithm, the Lady Comp will not currently sync with a smartphone app. This method is very simple to use. I do NOT RECOMMEND this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period.
  • Pearly Fertility Monitor: 99.3%
    This device is from the same people who make the Lady Comp and Daysy, and uses the same algorithm, but the Pearly device is bit smaller than the Lady Comp, larger than Daysy, and marketed separately. In this method women chart their period and use the Daysy device to take their basal body temperature (BBT) each morning. The device will then calculate fertile and infertile days. Unlike the Daysy Fertility Monitor, which is made by the same company and uses the same algorithm, the Pearly will not currently sync with a smartphone app. This method is very simple to use. I do NOT RECOMMEND this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period.
  • Daysy Fertility Monitor: 99.3%
    This device is from the same people who make the Lady Comp and Pearly, and uses the same algorithm, but the Daysy device is bit smaller and marketed separately. In this method women chart their period and use the Daysy device to take their basal body temperature (BBT) each morning. The device will then calculate fertile and infertile days. There is a smartphone app the device can sync with. This method is very simple to use. I do NOT RECOMMEND this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period.
  • Natural Cycles App: 99.5%
    In this method women chart their period, basal body temperature (BBT), and optionally, ovulation predictor kit (OPK) results. Then the proprietary app algorithm evaluates if you are fertile and infertile each day. This method also requires a paid subscription to use the app. This method is very simple to use. I do NOT RECOMMEND this method as the sole indicator of fertility for POSTPARTUM women who have not yet had their first period.
  • OvaCue Fertility Monitor / OvaCue Mobile Fertility Monitor
    This device is specifically marketed for TTC and not officially licensed for birth control use (TTA, trying to avoid pregnancy). However, some women have attempted to use it for TTA purposes. There is no reliable, studied protocol for using OvaCue to avoid pregnancy. The monitoring set comes with two sensors: the OvaCue Oral Sensor and the OvaCue Vaginal Sensor. The two OvaCue sensors can be used with either the stand-alone OvaCue device or your smartphone with the OvaGraph app to take a measurement. In this method women chart their period, OvaCue Oral Sensor results (measures saliva electrolytes), and OvaCue Vaginal Sensor results (measures cervical fluid electrolytes). Changes in the electrolytes (sodium and potassium) content are caused my changes in estrogen production, which indicate changes in the fertility cycle. When given sensor readings the stand-alone OvaCue device or the OvaGraph smartphone app then predicts your fertile window. Readings from the OvaCue Oral Sensor should indicate the start of the fertile window and readings from the OvaCue Vaginal Sensor should indicate the close of the fertile window (ie. that ovulation has occurred and you are in your infertile luteal phase). The device is fairly expensive, but it is only a one-time purchase with no additional cost to continue using. OvaCue is not officially recommended as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period.
  • OvuSense Fertility Monitor
    OvuSense is a wearable basal body temperature (BBT) thermometer that is “worn” in the vagina at night while you sleep. It also comes with an app to predict fertility based on BBT only. It is marketed towards women TTC (trying to conceive) and it is unclear if the app is useful for birth control purposes (TTA, trying to avoid pregnancy). It is fairly expensive. You need to pay for a subscription to the app (sold monthly or yearly) and a new Ovusenue Sensor (vaginal BBT monitor) every 12 months. OvuSense is not officially recommended as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period.
  • Ava Fertility Tracker
    This device is specifically marketed for TTC (trying to conceive) and not officially licensed for birth control use (TTA, trying to avoid pregnancy). However, some women have attempted to use it for TTA purposes. There is no reliable, studied protocol for using the Ava Fertility Tracker bracelet to avoid pregnancy. This is a wearable device that you wear on your wrist while sleeping. It tracks resting pulse rate, skin temperature (different from basal body temperature), heart rate variability, sleep, breathing rate, movement, perfusion, bioimpedance, and heat loss. It then syncs with the Ava smartphone app to predict fertility. This device is for women who regularly have a cycle length between 24-35 days long. For TTC purposes, it says “Ava has been shown to detect an average of 5.3 fertile days per cycle at 89% accuracy.” Ava is not officially recommended as a sole indicator of fertility status for birth control purposes, and it is especially NOT RECOMMENDED for birth control use by POSTPARTUM women who have not yet had their first period.

Additional Known Options

(More Information Needed)

These are options that are marketed to women for the purpose of detecting her fertile window, which I am aware of existing, but haven’t adequately researched. I do not recommend these methods at this time (and that may change in the future after I learn more about these methods).

References

A Super Long List of Fertility Awareness Based Methods (FABMs) | Starry-Eyed Pragmatist
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