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What is the Symoto Thermal Method?

The Sympto-Thermal Method is a natural form of birth control practiced by observing and recording two of our body’s fertility signs: basal body temperature and cervical fluid to actuately to dertermine our fertile and infertile windows accuractely and can be used  to plan or prevent pregnancy.

This method of fertility awareness is hormone-free, non-intrusive and has ben found to be 99.4% effective with perfect use.

This post is an overview of the 4 Sympto Thermal Method rules of what practising this method involves, and is intended to aid your decision if this method could be an option for you!

Natural Birth Control Introductory Posts
What is fertility awareness?
Your Natural birth control questions answered
8 mistakes to avoid when using natural birth control

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The 4 Rules of using Symoto Thermal Method as Birth Control

Before we get into all the juicy rules and specifics, a little disclaimer; if you do wish to practise the sympto-thermal method of Fertility Awareness as birth control, we recommend wholeheartedly to learn the thoroughly with a course or workshop (as well as using a barrier contraceptive method for a few cycles while charting and learning FAM). This post is intended as an introduction and starting point to help you decide is FAM is right for you and in no way substitutes thoroughly learning a method. For additional details, please see our full disclaimer.

And.. we have a great list of resources, online courses and FAM educators if you wish to learn more on our resources page. Let’s go…

Rule 1 – First 5 Days Rule (First 3 Days Rule if charting less than 1 year)

You are generally considered infertile the first 5 days of your menstrual cycle, unless you have ever had a cycle that was less than 25 days long. In case you have had a cycle that’s less than 25 days long or you’re in your first year of charting, you are generally considered infertile the first 3 days of your menstrual cycle.

During your cycle, there are typically 6 days when you are fertile. This is due to the combined fertility of a couple: whereas an egg will only survive for 12-24 hours after being released from the ovary, sperm can survive in fertile cervical fluid for up to 5 days.

During the first five days of your cycle, your body probably isn’t producing fertile cervical fluid, and ovulation is likely too far off for sperm to be able to survive until it occurs. So, you are considered infertile during that time. This rule applies regardless of how many days your period lasts. Any bleeding after the first five days of your cycle should be considered fertile, as the blood could mask fertile cervical fluid.

Note: This rule applies only if you observed a clear BBT shift 12 to 16 days prior to the start of your cycle. This confirms that the bleeding you experience is your period and not abnormal bleeding or ovulation spotting.

If any of your cycles in the past 12 months have been less than 25 days, you should consider yourself infertile for only the first 3 days of your cycle. This is to avoid the risk of getting pregnant due to early ovulation. Also, women who are beginning to experience signs of menopause should not rely on this rule, as they can experience major hormonal changes that could cause early ovulation.

If you experience spotting after your period ends, don’t assume you’re still infertile. Some women experience ovulation spotting, or spotting just before or during ovulation. Ovulation spotting, which is thought to be due either to a surge in estrogen levels or as a result of the egg rupturing through the follicle as it is released from the ovary, is actually considered to be very fertile cervical fluid.

Rule 2 – Dry Day Rule

You are generally considered infertile the evening of any day you observed that you had no cervical fluid.

The quantity and quality of your cervical fluid is key to whether you are fertile or not. Without cervical fluid, the vagina is very acidic, with a low pH of around 3-4. Because sperm requires a more alkaline environment (such as semen) to survive, it typically will not survive in the vagina for more than 1-2 hours if cervical fluid is not present. So, if there’s no cervical fluid, you’re not fertile. However, you need to wait until the evening to have unprotected sex to make sure your body doesn’t produce potentially-fertile CF during the day. FYI – arousal fluids and lubricants do not provide an environment in which sperm can survive, unless of course you’re using a lubricant specifically made
for sperm capacitation (but you’re probably not doing that if you’re using FAM as birth control, right??)

If you only experience one or two consecutive days of sticky cervical fluid and then revert back to dry days, you are considered safe again the evenings of each dry day.  But note that this means if you ever observe creamy or egg white cervical fluid, you should NOT consider yourself safe even if you have a dry day afterwards.

Sometimes, residual semen from intercourse can mask the presence of cervical fluid. So, if there’s any semen present in the vagina the day after intercourse, you should consider yourself potentially fertile, to be safe (to eliminate semen from the body so this doesn’t happen, you can do Kegels exercises after intercourse).

Note: Women will almost always experience a slight moistness at the vaginal opening. You’re still considered dry if there’s no cervical fluid present.

Rule 3 – Peak Plus 4 Rule

You are generally considered infertile the evening of the 4th day after your most fertile cervical fluid and once your CF has become infertile again, and you have observed a clear BBT shift.

As you approach ovulation, your cervical fluid will generally progress from Dry –> Sticky –> Creamy –> Egg White –> Watery as it becomes more fertile. The wetter your cervical fluid, the more fertile it is. After ovulation, your CF will begin to dry up. The last day of wetness that you experience before you begin to dry up is your Peak Day – generally the point during your cycle at which you are most fertile.  Note that I said the Peak Day is your LAST day of wetness, and not necessarily the day of the MOST wetness – so if you have lots of watery CF on one day, then a little watery CF the next day, and then sticky CF the following, the second day (with a little watery CF) would be your Peak Day.

You need to wait until the evening (6 PM or later) of the fourth day after your Peak Day until you can consider yourself infertile.

This is because it’s possible that you won’t begin to ovulate until two days after your Peak Day. At ovulation, it’s possible to release two eggs within 24 hours of each other (this is how fraternal twins are conceived), and since each egg can live a maximum of 24 hours, this adds up to 4 days after the Peak Day.

Note: women with Polycystic Ovarian Syndrome or other hormonal disorders can sometimes experience ‘false peaks’ in which their cervical fluid builds up from infertile or less fertile (sticky) to fertile (egg white/watery) and back to infertile again, but ovulation does not occur. This is why it’s especially important to keep track of your BBT as well as your cervical fluid, so that you can confirm ovulation.

Rule 4 – Temp Plus 3 Rule

You are generally considered infertile the evening of the 3rd day after your BBT shift.

A BBT shift that is sustained for at least 3 days confirms that ovulation has occurred. You need to make sure the BBT shift is sustained for at least three days because it’s possible that you don’t ovulate until 24 hours after your temperature shift, and again, it’s possible to release two eggs within 24 hours of each other (this happens 10{675b55e8130b20edc83d7a7372c667e99085718bc85437794f846651e9dba022} of the time, so don’t take your chances!). Also, you’ll want to ensure that the rise in your temperature was due to ovulation and not to something else, such as drinking alcohol the night before, fever, lack of sleep, etc. Look for three consecutive temperatures above your coverline.
Once a sustained BBT shift has occurred, you are considered infertile for the rest of your cycle.

How much time does it take to learn the method?

Shorter than you’d probably expect! The rules can seem a bit confusing and overwhelming in the beginning, but don’t worry, it doesn’t take long before you commit these rules to memory.

Some women will feel confident reading the relevant chapters in Taking Charge Of Your Fertility, others will prefer an in person workshop, or an online course.

After learning the method, it usually takes two to three cycles observing and tracking to feel confident enough to use this method as birth control. After that, charting usually takes just a few minutes each day; 1 minute to take your temperature upon waking in the morning and another couple of minutes to record your fertility signs in an app.

Kindly note, this post is intended as an introduction and starting point to help you decide is FAM is right for you and in no way substitutes learning a method thoroughly! For additional details, please see our full disclaimer.
We have a great list of resources, online courses and FAM educators to learn more so please see our resources page.

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