Fertility awareness also called natural family planning or natural contraception is a set of practices used to determine the fertile and infertile phases in a woman’s mentrual cycle. This is achieved by tracking the various changes that take place during the menstrual cycle.There are five fertility awareness methods, namely: the cervical mucus (or billing) method, the temperature method, cervical position and opening, the calendar method, and ovulation predictor kits (OPKs). Fertility awareness methods do not necessarily aim at pinpointing the exact day of ovulation. However, they will help you to predict your fertility window and if you know your fertility window, then you can plan on when to have sex or when not to in order to avoid pregnancy. With sufficicient experience or very regular mentrual cycle, you might be able to predict the exact day of ovulation.

You must not necessarily have sex on the day of ovulation itself in order to get pregnant since the sperm can survive for up to 6 days in the female reproductive tract. But the closer you have sex to the day of ovulation, the higher your chances of getting pregnant. One method might not be enough for you to detect your fertility window since other factors like stress, depression, sickness, or medication can affect one method more than the other. Therefore, a combination of 2 or more fertility awreness methods is usually recommended.

Details about the five main fertility awareness methods are provided below including how they are used to identify the fertility window. 


Cervical Mucus Method

Tracking changes in the amount or nature of the cervical fluid helps to predict when you are likely ovulate. For this method to be successful, you may need to observe the following:

  • Track your mucus changes for at least 3 months
  • Be ready to forgo sex for an entire month 

The following figure shows the cervical mucus  cycle.

Changes in the Cervical Mucus

  • During menstruation: Blood flow covers mucus so you might notice no observable change in mucus. Since you can’t feel the mucus during this period, consider it unsafe. This is true for people with very short menstrual cycle.
  • Few days after menstruation: Just after menstruation you may observed a brownish white discharge which is a result of old blood leaving the vagina. But after this you will see no discharge or mucus for few more days. These are called dry days. The length of your dry days depends on the length of your menstrual cycle. Dry days are safe days for sex.
  • Before the start of your fertility window, your body starts to make mucus. This mucus is usually cloudy or white with a yellow tinge and appears sticky or tacky in consistency.
  • As you enter your fertility window, the cloudy and sticky mucus gradually changes to white creamy, then to wet and watery and finally to clear and slippery like raw egg white which peak at ovulation. Note that as you approach ovulation, this watery mucus becomes more wet and abundant. Egg white cervical mucus (EWCM) helps to nourish and transport the sperm. Its formation is triggered by estrogen.
  • About 3 days after ovulation the egg white cervical mucus dries up into cloudy and sticky mucus. This will then be followed by few more dry days. These are all safe days to have sex.
  • Your period starts again and the cycle repeats.

Vaginal or Mucus Abnormalities

Several factors such as infections, birth control pills, medications, surgery on the cervix, breastfeeding, supplements and vaginitis will alter the colour, consistency and odour of your vaginal discharge. The following changes in your vaginal mucus or vagina as a whole will warrant immediate doctor consultation:

  • Gray discharge is indicative of a bacteria vaginosis
  • Dark yellow or greenish mucus may suggestion an infection. Yellowish white mucus may however be normal.
  • Pink discharge at the beginning of menstruation or after sex is normal but outside these 2 scenarios, then it’s a call for concern.
  • Red or brown discharge may occur before or after menstruation. Outside this, then it may be a call for concern.
  • Lumpy or frothy discharge
  • Strong or foul smelling discharge
  • Pain, burning or itching in or around the vagina
  • Rashes, sores or redness

How to check your cervical mucus?

  • Wash your hands thoroughly and dry them clean
  • Sit on the toilet pot, squat or stand up but put one leg on the toilet sit or bathtub edge.
  • Insert either your index or middle finger gently and carefully into your vagina. Get samples close to your cervix but if you are producing enough watery mucus, you might not need to go very far.
  • Now remove your finger from your vagina.
  • Look at the mucus
  • Check the consistency of the mucus
  • Rub the mucus between your fingers (thumb and index finger or middle finger and index finger)
  • Press the mucus between this same fingers and pull

What are your observations?

  • Is it sticky and scanty or crumbly? If yes then you have not yet entered into your fertile window.
  • Is it creamy? If yes then ovulation is underway
  • Does it appear wet, watery or stretches slightly? If yes then ovulation is very close
  • Is it very wet and watery or does it stretches between your fingers even for an inch and resembles raw egg white? If yes to this question, then ovulation is about to take place.

Record your findings on a chart

On your chart, make sure you record the following; the length of your cycle, the days you had sex in between, note whether you used condom or not and the mucus changes as dry days, sticky days, cloudy days, wet days, slippery days. Also note the colour of the mucus or discharge. You might use S for sticky, C for creamy, W for wet and EW or EWCM for egg white cervical mucus.

Other tips for checking cervical mucus

  • Check for any discharge on your underwear
  • Check your toilet paper after urination. Otherwise before you pee, you can wipe the opening of your vagina with a white tissue paper and then check the colour and consistency of any mucus if present.
  • Take note of any sensation of wetness or dryness of your vulva throughout your cycle. Wet sensation is a sign of fertility mucus present. Such wet sensations may be absent for women in their late 30s or in their 40s since they usually produce less fertile mucus.
  • Drink enough water. This allows you to produce quality mucus and will facilitate your observations.

Caution when recording cervical mucus changes

  • Don’t check your mucus just before or after sex. Sexual arousal or semen will alter the nature or consistency of the mucus. If possible avoid sex for a whole month when you use the cervical mucus method for the first time. Othewise, use a condom.
  • Don’t check egg white cervical mucus (EWCM) after douching. This can either reduce your chances of getting pregnant if that is your goal or affect the consistency and colour of the cervical mucus.
  • Women with polycystic ovarian syndrome (PCOS) get multiple patches of cervical mucus. If you fall into this category, then you might want to supplement mucus tracking with other methods such as BBT and cervical position. This will help you to know exactly which of these patches of mucus the right one was.
  • Some women naturally experience second EWCM-like mucus just before menstruations starts. This second mucus is not a sign of fertility.
  • Not every woman gets egg white cervical mucus. This may be normal in some few percentages of women but could be a sign of infertility. Talk to your doctor if you are trying to conceive
  • Not every EWCM looks ideal. Meaning it might not really look like raw egg white.
  • Much changes in your EWCM might not be noticeable until when you are about to ovulate.


Temperature Method

The temperature method involves recording your basal body temperature (BBT). BBT is your temperature when you are at rest. That is, just before you get up from bed. This temperature increases after ovulation as a result of an increase in the hormone progesterone and will stay high until the next menstrual cycle. In the event that you get pregnant, your BBT will remain high since progesterone levels will be high as well during pregnancy. Unlike cervical mucus which can help you predict when you will ovulate, BBT does not. It tells you when ovulation occurred only when it has already happened. But you can achieve a better prediction when you record BBT for about 12 months.  

Why use BBT to monitor fertility changes?

  • It helps to confirm when ovulation occurred if use in conjunction with the cervical mucus method. This gives you a greater confidence on what you are doing. This is true because you will likely observe egg white cervical mucus (EWCM) on the day before or on the day of ovulation itself. Also about 3 days after ovulation this EWCM will dry up to a sticky and white mucus.
  • In case your cervical mucus is affected by medication, illness or other factors, BBT can still give you a hint on when ovulation occurred.
  • BBT chart can give you a hint but not a necessary a confirmation on whether you are pregnant or not. If you observed a triphasic pattern on your BBT chart which occurs about 1 week after ovulation. The there is a high probability that you are pregnant.
  • BBT can be used to determine if you have an irregular cycle or ovulation problem

Drawbacks of BBT Method

  • Tells you the approximate day ovulation occurred when it has already happened. Does not predict it before it happens. 
  • Not reliable if you work night shifts or have irregular sleeping pattern that causes you to wake up every night and/or move around. Other factors that will affect BBT are illnesses, stress, depression or when sleeping with your mouth open.
  • You can get EWCM but never experienced an increase in basal body temperature. There might be several reasons for this including: no ovulation might have taken place or you may be recording your temperature wrongly
  • Some few percentages of women do not naturally get an increase in basal body temperature even though they are ovulating.

If you feel concern by changes in your basal body temperature then talk to your doctor for advice or fertility testing.

How to record your BBT?

  • Get a BBT chart; see free resources for charts, use charting software or calendars. Otherwise you can check on samples and make your own.
  • Get a basal body thermometer at the nearest pharmacy
  • Start charting from day 1 of your menstrual cycle and record throughout your entire menstrual cycle. As a beginner it is very necessary but with experience, you may start recording after menstruation or close to ovulation.
  • Every morning before getting up from bed. Make sure you don’t move an inch from your bed. That is, don’t sit up, get up, or walk around. Keep you thermometer within arm’s reach the night before you sleep.
  • Temperature must be taken at the same time every day and not more than 30 minutes apart. If it’s 5 am today, make sure tomorrow also it’s either 4:30 am, 5 am or 5:30 am. Outside that range then you are out of order.
  • You must have at least a straight 4 h of sleep
  • Same thermometer must be used throughout.
  • Record both the BBT as well as the time on your chart
  • Also record the days you are having sex every month.

How will you know that ovulation has occurred?

As your cycle progress, you may experience a rise and fall in your temperature much like a series of spikes. Do not be concern about these spikes but rather be concern on the overall pattern or overall average in which case you will see a biphasic pattern after ovulation. If you get 3 temperature spikes in a row which are higher than the previous average, you may say that ovulation occurred on the day before the first higher spike was observed.

Ovulation may not occur on the same day every month except for special cases. It may occur over a range. That is you may notice that it always comes somewhere between day 11 to 15. That is why it is necessary that charting with BBT be done for not less than 3 months but if your circle is irregular then you might even need to do it for up to 12 months straight.


Cervical position and opening

Your vagina is like a tunnel and at the end of that tunnel is the cervix. The cervical os is the opening in the cervix which connects your vagina and your uterus. The cervix can shift position and change in its nature throughout the menstrual cycle. During menstruation and infertile days, the cervix appears lower in the vagina canal and feel firm to the touch just like the tip of your nose. During this time, the cervical os is closed except during menstruation where it partially opens to allow passage of the sperm.

As you enter your fertile window, the cervix rises up the vagina and appears soft and moist. It becomes softer and moister as you approach the peak of your fertile window which is ovulation. The cervical os is open throughout the fertile window to allow passage of the sperms. In the event that pregnancy occurs, the cervix will remain up and softer but the cervical os will be tightly closed.

How to check your cervical position

  • Choose the best time to do it. It is usually best after a shower or bath
  • Wash your hands thoroughly
  • Position yourself by sitting on the toilet, squatting or standing with one leg on the bathtub edge or toilet.
  • Gently and carefully insert 1 or 2 fingers into the vagina and try to feel the cervix located in the upper front or top.
  • Repeat this for several cycles until you master the changes.

This method is very useful for women who are experiencing several patches of egg white cervical mucus in which cases they can’t tell which one is the right one. But the position of the cervix can help confirm the right one. The right one can further be confirmed by an increase in BBT.


The Calendar Method

The calendard method also called the rhythm method or calendar rhythm method helps you to predict your most fertile days by recording the length of your menstrual cycle over several months. This method requires patience as you will need to keep records for at least 6 months but 12 months is best.

How the Calendar Method Works

  • Day one of your menstrual cycle is the first day you started menstruating.
  • Record the first day of your menstrual cycle for each month
  • Calculate the total number of days between each cycle. For example, if in January your menses started on the 21st and in February it started but on the 19th, then the total number of days in the January menstrual cycle will be 29 days.
  • Repeat this for at least the next 6 cycles

Predict the first fertile day of your current cycle

  • Choose the shortest cycle and subtract 18 from it. For example let our shortest day be 28 day. So 28 minus 18 will give 10.
  • From day 1 of your current menstrual cycle, count 10 days (including day 1) and mark that day as X. This day is your first fertile day. For example if day 1 of your current menstrual cycle is on the 7th then day 16 of that cycle should be mark as X. Avoid vaginal sex on that day or use a condom if you want sex badly.

Predict the last fertile day of your current cycle

  • Choose the longest cycle in your records and subtract 11 from it. For example let our longest day be 30 days. So 30 minus 11 will give 19.
  • From day 1 of your current menstrual cycle, count 19 days (including day 1) and mark that day as Y. This day is your last fertile day. For example if day 1 of your current menstrual cycle is on the 7th then day 25 of that cycle should be mark as Y. This is your last fertile day and after this day, you can start having unprotected sex.
  • So from this, your fertile window will be from day 16 to day 25. That is 10 days (including day 16)

Disadvantages of the Calendar Method

  • It only predicts but your fertility window and doesn’t tell when exactly you are most fertile
  •  It’s not useful if all your cycles are shorter than 27 days
  • Not suitable if your cycles vary in length all the time. There must at least be months whereby your cycles are same. Therefore, not good for cycles that are too irregular.
  • It should be used in combination with other methods for better accuracy


Ovulation Predictor kits (OPKs)

OPKs are similar to a home pregnancy test, it comes with 2 lines. If test line is darker than the control, then ovulation is about to take place. They measure luteinizing hormone (LH) levels. LH is a hormone which triggers ovulation and it will spike or surge 24 to 36 h before ovulation.

Advantages and disadvantages of using OPKs include:

  • Easy to use and not tedious like recording your basal body temperature
  • Predict when you are likely to ovulate
  • They can be used at any time of the day and does not require you invading your private parts especially for women who are not comfortable with it. Urine is usually enough.
  • Some people are colour blind and might not be easy for them to detect the difference between the test line and the control line
  • It can give a false positive result in that even though the test show positive but you will not ovulate
  • Women with polycystic ovarian syndrome (PCOS) can get multiple positive and false results. Making the test kit useless.
  • LH surge occur 24 to 36 hour before ovulation. It is therefore important that you have a mastery of your menstrual cycle. Irregular cycles can make you miss the right time to test in that you test too early or a little bit late. This can make the use of OPKs very expensive

Useful Resources

There exist free websites and apps to learn and chart your fertility signals. These resources will assist you in successfully using the fertility awareness methods.

Fertilityet.org.uk: Provides fertility education and training on how to use a fertility chart.

Fertilityfriend.com: Provides education and training, question and answers, discussion forums, gallery of fertility charts and lots more. It has both a free and a paid version.

Myfertilitycharts.com: Provides free fertility calendars for you to track you changes in your menstrual cycle. It has both a paid and a free version as well as a mobile app. The paid version comes with additional features.

Mymonthlycycles.com: Provides free fertility calendars for you to track you changes in your menstrual cycle and will interpret changes for you. You can also add notes, track PMS symptoms, doctor appointments, and get email reminders and much more.

Tcoyf: Provides free downloadable charts and also allows you to do charting online through Ovagraph.com. Ovagraph comes with a mobile app and you can store as much data as you wish.