Fertility awareness is the practice of observing and charting the physical signs of fertility that occur during the menstrual cycle. You can use these signs to determine the days you are fertile and the days you are not.
Even though we often grow up thinking we can get pregnant at any time if we are not careful, we are actually only fertile for a reasonably short window of time during each menstrual cycle.
If you learn how to identify the signs of fertility in your body, you can use this information to either naturally avoid pregnancy, achieve pregnancy or as a tool to monitor your overall health.
Please note that this article is meant as an informational piece for your personal education. I am not a qualified Fertility Awareness Educator nor am I a medical practitioner. Please refer to my medical disclaimer for more information. All information in this article is based on my own research. I have listed all of my resources at the bottom of this post.
Disclosure: Some of the links on this page are affiliate links. Please refer to my Affiliate Disclosure for more information.
What are the observable signs of fertility?
There are three primary signs of fertility. They are:
- Waking basal body temperature (BBT)
- Cervical fluid or cervical mucus
- Cervical position
Waking Basal Body Temperature (BBT)
> What is basal body temperature?
Your basal body temperature or BBT for short, is the temperature of your body when it is at rest.
In order to track your BBT as a sign of fertility, you need to take your temperature each morning and record it on a paper fertility chart or in a fertility charting app.
> Why is basal body temperature a sign of fertility?
Basal body temperature can be used to show that you have ovulated. When you chart your temperature every day, you will be able to see a visible shift in the temperatures post-ovulation when compared to the temperatures prior to ovulation. This will be a sustained rise in your temperature that will remain until your next period.
This is because, prior to ovulation, the dominant sex hormone being produced is oestrogen. After ovulation, progesterone takes over. Progesterone is a heat-inducing hormone which causes the basal body temperature to rise. The temperature will then remain in this higher range for the rest of the cycle (until the next period occurs).
To really understand this rise in temperature, I’ll let this perfect quote do the talking:
“This shift in temperature is one of the ways your body prepares for pregnancy. Similar to the way a mother hen sits on her eggs to keep them warm, your body temperature rises to keep your eggs warm during the second half of your cycle”.Lisa Hendrickson-Jack, The Fifth Vital Sign
If pregnancy were to occur, progesterone would continue to be produced throughout most of the pregnancy.
If pregnancy does not occur, the basal body temperature will remain high for 10 -16 days before progesterone levels drop again and you begin your next period.
You would be able to confirm pregnancy, if charting correctly, by a sustained temperature shift for 18+ days post ovulation.
It is important to note that your temperature shift can only confirm that ovulation has already occurred. It cannot predict when ovulation is going to occur. You can use the other fertility signs for this.
The released egg only survives for 12-24 hours before it disintegrates. So, by the time you see a rise in temperature to confirm ovulation, the egg will have already been released and be on it’s way to meet any awaiting sperm.
If you want to learn more about charting your Basal Body Temperature, then click this link to read my BBT Charting post.
Cervical Fluid or Cervical Mucus
Do you pay much attention to your vaginal secretions? It’s not really great dinner time conversation which unfortunately means a lot of us are misinformed in regards to what is really going on down there!
If you’re like me, you may have only ever referred to your vaginal secretions as discharge. I know I always felt like there was something dirty and unclean about my vagina when there was a lot of moisture. Can you relate?
Instead of using the word ‘discharge’ you should get familiar with the terms ‘cervical fluid’ or ‘cervical mucus’. These terms can be used interchangeably and are the proper terminology for the normal cyclical secretions of your vagina. Yes, sometimes you may experience discharge that is the result of infection, but this is not to do with fertility and will not be discussed in this article.
> Cervical fluid throughout your cycle
When you start to pay attention to your cervical fluid, you may be surprised to find it follows a pattern throughout your cycle. Like most happenings of the body, cervical fluid serves a very important purpose. The purpose of cervical fluid is to keep sperm alive and help transport it to the egg!
Without fertile quality mucus to keep it alive, the sperm will actually die within a few hours! I listened to an interview with Lisa Hendrickson-Jack in Maisie Hill’s The Flow Collective membership program. I couldn’t help but laugh when Lisa said this:
“Outside of your fertile window, your vagina is super hostile. It’s like a sperm killing machine! The cervix is closed. Vagina is acidic and the sperm just die.”Lisa Hendrickson-Jack in conversation with Maisie Hill
Let’s consider your cervical fluid throughout each stage of your cycle.
> Wet vs Dry Days
There are actually many different types of cervical fluid that can occur during the cycle. From sticky, to creamy, to eggwhite, it can get a little confusing to identify. For the purposes of this article, which is just a basic overview and by no means a comprehensive guide, I think it will be easiest to start out thinking of it as simply wet vs dry.
I first got a good grasp of the wet vs dry concept when I took the Debunking Ovulation masterclass from Nat Kringoudis. I took this masterclass when I was 28 years old. That means I had been experiencing a menstrual cycle for 14 years without having this knowledge! How frustrating!
In this masterclass, Nat explained how your period (days of bleeding) will typically be followed by several dry days before you start to notice some moist days, continuing into wet days up until ovulation. After ovulation you will go back to dry days again until your next period.
I put this concept into a diagram to show visually what is happening throughout a typical cycle:
What is actually happening to cause this is that oestrogen levels are rising. Oestrogen is responsible for producing cervical fluid in preparation for ovulation
As Toni Weschler says in her book Taking Charge of Your Fertility:
“Cervical fluid is to the woman what seminal fluid is to the man.”Toni Weschler – Taking Charge of Your Fertility
Men are fertile every day, so they produce semen every day. Women are only fertile around the time of ovulation, so they only produce cervical fluid around this time.
> What does cervical fluid have to do with fertility?
The role of cervical fluid is to protect, nourish, transport and filter the sperm.
The cervical fluid provides an alkaline environment to protect the sperm from the otherwise acidic “sperm-killing” vagina.
Cervical fluid provides a nourishing environment for sperm which keeps it alive for up to 5 days, sometimes longer, before ovulation. This is why it’s important to observe your cervical fluid patterns to identify your fertile window. You can’t just wait until a shift in temperature to confirm ovulation. By the time ovulation occurs, you may have already been fertile for days.
The sperm also hitches a ride in the cervical fluid. Cervical fluid is the mode of transport to get the sperm to the egg. If you look at fertile quality cervical fluid under a microscope it has channels that the sperm can swim through with a clear route to the egg. Non-fertile quality mucus looks more like a hashed pattern which blocks the sperm from getting through.
The channeled cervical fluid also acts as a filtering mechanism to filter out the low quality sperm from the high quality sperm. The sperm that moves freely and efficiently through the channels are the strongest swimmers. Any sperm that doesn’t swim as well will be left behind.
> Peak cervical fluid vs non-peak cervical fluid
There are different types of cervical fluid, as I touched on earlier. Under some fertility awareness methods, these can be categorised into peak and non-peak fluid. Peak fluid is usually considered the most fertile and can be watery, slippery, clear or eggwhite-like. However, unless you are working with a qualified fertility awareness instructor who guides you otherwise, the presence of any cervical fluid should be considered fertile. Although some types of cervical fluid may be more fertile than others, all types can potentially be hospitable to sperm!
From a contraception perspective, you don’t want to make the mistake of thinking you can only fall pregnant with eggwhite cervical fluid. Likewise when trying to conceive you should be going for gold in the presence of any fluid to maximise your chances of conceiving.
> Cervical fluid after ovulation
As we previously learnt, after ovulation oestrogen levels drop and progesterone levels rise. Progesterone dries up the cervical fluid and the fertile window comes to an end.
There are many different fertility awareness methods and they may have differing views on when the fertile window ends. If you are planning to use fertility awareness as your method of contraception, you should work with a qualified instructor. They can help you to understand the intricacies of your chosen method in order to effectively avoid pregnancy.
A final primary sign of fertility is cervical position. You don’t have to monitor this sign and most fertility awareness methods consider this as an optional sign. However, I will still cover it here as it’s pretty interesting to understand!
> Your cervix moves throughout the cycle
Your cervix is a wonderful thing! My eyes were truly opened to the wonders of the cervix when I read this article from Women’s Health magazine:
And when I finally committed to finding my cervix by watching this video from Put A Cup in It:
Your cervix is the lower part of your uterus that protrudes down into your vagina. For more information regarding the cervix and the rest of the reproductive system check out this earlier post Our Female Reproductive Anatomy.
The cervix prepares for pregnancy, under the influence of oestrogen, by softening and opening around the time of ovulation. This allows the sperm to swim through the uterus and to the fallopian tubes. The cervix also rises/moves up higher. Some suggest this is a biological process of ensuring only the strongest sperm survive as they have to swim further to reach the opening of the cervix.
After ovulation, under the influence of progesterone, the cervix will lower and feel firmer and closed. The cervix will reopen slightly again to allow the menstrual fluid to pass through from the uterus during the menstrual/bleeding phase of the cycle.
> How to check your cervix
Some people may not wish to check their cervix as a sign of fertility and that’s okay! But if you are interested to use this as an additional sign of fertility, you can perform an internal check with your finger. I like to do this when I’m in the shower. I highly recommend watching the video I previously mentioned How to Find and Measure your Cervix to understand what you are feeling for.
For most of the cycle, it will probably feel much the same, when your cervix is low, firm and closed. But when you are fertile you should be able to feel the difference as the cervix will move higher and become soft and open.
In order to notice the difference though, you will need to check each day. Lisa Hendrickson-Jack recommends checking your cervical position every day for one full cycle. You need to commit to every day so you get to experience the change around ovulation.
Charting all your signs
That concludes the three signs of fertility that you can observe in your body throughout your cycle. It’s important to make sure you record and chart these observations daily. You can then identify the patterns when you look back over the whole cycle. If you don’t record them, you won’t remember!
Most paper chart templates and charting apps will have the functionality to record not only your basal body temperature, but also your cervical fluid and cervical position observations.
Want to learn more about Fertility Awareness?
If you are interested to learn more about fertility awareness for contraception, conception or just as a tool to monitor your overall health, I highly recommend the following books:
Taking Charge of Your Fertility by Toni Weschler; and
The Fifth Vital Sign by Lisa Hendrickson-Jack.
You can also find Lisa on her website Fertility Friday. As well as the Fertility Friday Podcast and on her Instagram.
I hope you have found this article helpful to understand what fertility awareness is and what your fertile signs are. As previously mentioned, I am not a Fertility Awareness educator and I am not a health practitioner. Please refer to my medical disclaimer for more information. Everything I have written about in this article has been based on my own research and reading in this topic.
My resources were:
Click this link to go to my recommended resources page. On this page I share heaps of great things to help you have a better period.
Want to learn more about the female reproductive system? Click this link to read my earlier post about the female reproductive anatomy.
The Better Period
Ellie Heasman is a period blogger and founder of The Better Period. Ellie helps people on their journey to a better period through introducing them to the world of menstrual cups and period underwear, and sharing knowledge about the menstrual cycle and fertility awareness. You can join in the better period conversations on Instagram @thebetterperiod_ or find out more about Ellie here.