It’s a thermometer! And it only costs $10.00!
This simple and informative technique is called Basal Body Temperature Tracking
Basal Body Temperature Tracking is the perfect tool for you if you:
- experience PMS
- have painful periods or cramping before your period
- get hormonal acne or hormonal headaches
- experience mid-cycle spotting or premenstrual spotting
- you’re trying to conceive
- you’re trying NOT to conceive
- you have a really long cycle ( > 35 days)
- you have a really short cycle (< 28 days)
- you have an irregular cycle (who even knows when your period comes!)
- you have just come off of birth control
- you’re still on birth control
- you’re curious about your body and want to be empowered!
If you haven’t read my blog titled “How Stuff Works: Pills & Periods” you should read it first to get a better understanding of hormone physiology and the menstrual cycle. In extremely simplistic terms, the first half of your cycle- the follicular phase– is dominated by estrogen. Once you have ovulated and are in the second half of your cycle- the luteal phase– it is dominated by progesterone. What is unique about these 2 hormones is that they have different thermogenic effects, this means they change your body temperature. If you track your body temperature daily you can chart your hormone patterns and figure out what’s going on in your unique body. Not every girl’s cycle is a perfect 28 days with ovulation on day 14!
Here is an example of a BBT chart using an app called Fertility Friend:
- The lower body temperatures for the first 14 days show that this gal is in the follicular phase of her cycle
- The red cross denotes ovulation. You will see that ovulation is the last day of low temperature. Once the temperature peaks, she has officially ovulated
- As you learned in my other blog post, progesterone is secreted from the corpus luteum which is a byproduct of the egg. Progesterone is thermogenic, as you can see from the elevated temperatures. She is in the luteal phase starting day 15
- On day 26 you can see that her temperatures are falling, this shows that progesterone is also decreasing and the endometrial lining will be shed
- You may have noticed that the BBT tracking method is a hindsight method. You will not know that you have ovulated until after you have ovulated and you see a temperature peak
- After tracking a couple of months of your cycle you will see that you always ovulate at the same time in your cycle so you can plan accordingly for future months
Sweet! Now how do I do this?
I highly recommend you download the fertility friend app so that you can easily record your temperature and the app will make you a beautiful chart and show you when you ovulate with a giant red cross.
Here are the rules:
- Take your temperature as soon as you wake up in the morning, before doing anything else. The goal is to hardly move
- Take your temperature at the same time every morning, or as close to the same time as possible (within a 30 minute window)
- Take your temperature after a solid few hours of sleep (minimum 3 hours)
- If you want to get really fancy you can take your temperature using a special BBT thermometer that has more than 1 decimal place
- Enter your data on your chart in your Fertility Friend app
- The rise in temperature is usually about 0.4 degrees Fahrenheit or 0.2 degrees Celsius, but the rise may be as slight as 0.2 degrees Fahrenheit or 0.1 degrees Celsius or even less in some cases. Great variability is possible.
- More important than the value of the rise, is the overall pattern of the chart. Fertility Friend helps you determine ovulation based on the pattern of the chart and all fertility signs. It’s an awesome app