An Honest Review of Fitbit for Menstrual Cycle Tracking

You may know that the Fitbit app has some built in menstrual cycle tracking features, but many people do not know that it has other features that may be useful for menstrual cycle tracking. In this article, I will review the pros and cons of the Fitbit app as it relates to cycle tracking for people who ovulate. For context, I use a Fitbit Charge III.

The most basic feature that Fitbit offers for cycle tracking is recording bleeding dates of menstruation and then displaying a predicted fertile window based on average cycle length.

The pink bar represents the length of menstruation. The blue bar represents a predicted fertile window. The flower symbol represents predicted ovulation.

The user needs to remember to input menstuation each cycle. Once it is inputted, Fitbit will generate the blue fertile window. This fertile window should NOT be used for avoiding pregnancy, as it is only based on cycle length and not real-time fertility signs like cervical mucus or basal body temperature.

Once menstruation is entered, it will also begin a countdown until your next predicted menstrual cycle.

Countdown until menstruation in the app.

Unfortunately, I do not find this basic feature very useful for anyone who has any cycle variation. Even though my cycle length has increased over the last year, Fitbit has not automatically updated my cycle lengths. The app does not appear to be very adaptive without user input.

In addition to tracking bleeding the app offers options for:

  • Mood
  • Plan B (morning after)
  • Ovulation tests (better called luteinizing hormone tests)
  • Cervical mucus (Taking Charge of Your Fertility categories)
  • Cyclical symptoms like acne

It is rather disappointing that the app does not include options to mark pregnancy when it occurs, especially since we know that this changes daily calories burned and heart rate, to name just two effected areas of the app.

A really cool feature that I do like is the ability to show cycle trends like flow intensity and cramps. The same screen that displays this will also let you scroll through all past cycle lengths.

In the settings of this screen, you can also decide to toggle off predictions. For people avoiding pregnancy, I do recommend either ignoring or toggling off predictions in the Fitbit app. The app allows you to choose your current birth control method as well.

Outside of the designed menstrual cycle tracking features, I want to highlight resting heart rate as a potential exciting thing to track for those who are not taking hormonal contraception. Why do you need to not be taking hormonal contraception to utilize the heart rate feature for menstrual cycle tracking? Hormonal contraception suppresses ovulation, and ovulation changes our heart rate charts!

To learn more about resting heart rate and the menstrual cycle, read my previous post here.

You can see my heart rate falling during menstruation around April 10th, and then rise during my fertile window and luteal phase.
Menstruation began when my heart rate dipped below 70 on this chart. Ovulation likely occured around the third raised heart rate in this close-up.

Heart rate in people who are ovulating is at its lowest point during menstruation, rises during the fertile window, and continues to be elevated in the luteal phase.

When heart rate begins to drop again, this is an excellent way to predict menstruation will soon occur. For example, I have been tracking my heart rate in Fitbit for 2 years, and I always bleed when my heart rate dips back down to 70 beats per minute after my luteal phase!

I do think this feature is worth tracking for anyone interested in a more precise period prediction than cycle length. If you have Fitbit premium, you can also find a setting for sleeping heart rate under restoration. This may be more steady than resting heart rate for some individuals.

Lastly, I want to address Fitbit temperature for menstrual cycle tracking. Unfortunately, wrist temperatures are not a compatible parameter for fertility awareness when it comes to avoiding or achieving pregnancy. It can be incredibly erratic. When we track temperature, we want the temperature as closest to the core as possible.

Fitbit does not give precise temperatures, instead it gives deviations from a range. I likely ovulated near 18, 19, or 20 on the photo above. While Fitbit did detect a slight shift, it is not particularly clear, and it dropped back down.

As depicted above, my luteal phase the previous month was extremely undefined, and I could not determine a confirmed temperature shift with it.

For now, I do not recommend Fitbit for precise temperature tracking. Instead, I recommend a basal body thermometer.

Conclusion

Fitbit offers some really unique options for cycle tracking, but it should not replace your birth control or fertility awareness method. The heart rate feature may be useful for identifying cycle phases, but the temperature readings are not suitable for tracking cycle phases.

What is Walking Sensation?: How to Check for Vulva Sensation While Going About Your Day

This article was originally published on fertilityawarenessmethodofbirthcontrol.com


While some fertility awareness based methods use wiping sensation, a large majority of sympto-thermal methods (as well as mucus-only methods such as the Billings Ovulation Method) use some variation of walking sensation.  Walking sensation is the feeling someone experiences at the vulva while going about their day to day activities. A good way to think about it is what it feels like to feel menstruation begin. Most people understand that this causes a wet feeling at the vulva without even needing to look to see the blood. Likewise, walking sensation can be felt at the vulva without needing to look for visible mucus. 

This feeling might feel like something is falling out of your vagina. It could feel moist, wet, sticky, lubricative, slippery, or similar terms. This sensation opens the fertile window even if no visible mucus is seen. In fact, it is common to have walking sensation open the fertile window before any mucus is seen. It is also common for slippery / lubricative / wet sensation to be set as peak day (depending on your method rules!). Again, this would count as a fertile day even without visible mucus being seen.

Walking sensation is a practice in mindfulness. It involves tuning into the nerves at the vulva as you go about your day. Notice how it feels when you walk around, exercise, or otherwise move throughout the day. Wearing tight pants or synthetic fabric underwears can make it harder to feel. If you are having trouble tracking walking sensation, consider wearing a skirt or dress for a full cycle. This can be helpful if you are having trouble tracking it. Another common suggestion to help learn it is to “chart blind” for one full cycle (obviously you will need to refrain from unprotected sex if changing up your method!). Charting blind means charting your sensation without looking at your visible mucus. This forces you to rely on the feeling at the vulva. Note that the Billings Ovulation Method which relies on walking sensation as the primary sign has done small studies with blind women who were able to chart their patterns with it while never being able to see visible mucus. 

If you are interested in learning more, reach out to an instructor. If you want to use it as a part of a mucus-only method, the Billings Ovulation Method focuses more on it than any other existing method. I personally teach this sensation in my Billings Ovulation Method class.