For years, the Oura Community has been sharing their patterns and following their body’s cycles manually with the help of their Oura Rings. Now, we’re excited to announce there’s a feature that helps accurately track your period.

Period Prediction Beta helps you track your period according to your body rather than your calendar. While many period tracking tools exist, they base their predictions on numerical values like cycle length or your calendar, rather than reading signals directly from your body as they change. In fact, the idea that most women’s cycles are 28 days long is a common misconception and may only represent a small portion of the population.[1] Additionally, your cycle length will likely change with age.

Oura believes that your tracking tool should adapt with you. Period Prediction Beta automatically updates the predicted start date of your next period based on your own body’s natural temperature shifts with hormones at different phases of your menstrual cycle. Oura’s Period Prediction Beta feature gets smarter over time as it gets to know your personal cycle rhythm, and it improves its predictions based on your feedback.

Read on to learn how you can use this feature to plan ahead and understand your personal cycle better. 

NOTE: Our Period Prediction Beta feature is designed to work for individuals who have natural temperature patterns in their cycle. If you are using hormonal contraceptives (e.g., birth control or an IUD), become pregnant, or are on hormone replacement therapies, the algorithm will not be able to accurately predict your period. 

What’s New?

Period Prediction Beta is designed to serve individuals with all types of cycles – long, short, variable, and regular. It is now available for all Oura Ring Generation 3 members.

Automatic Alerts 

Oura will notify you 6 days in advance of your predicted period start date and prompt you again the day before so you’re never caught off guard.

Advanced Predictions  

Oura’s temperature sensor generates 1,440 data points each day and is validated to measure changes as precisely as 0.13°C (0.234°F). This rich temperature data enables Oura to start predicting your period up to 45 days out and update that prediction as the patterns in your body shift.

Gets Smarter With Use

Period Prediction Beta is designed to get smarter with use. When you first start using Period Prediction Beta, your estimates will be based on your past cycles – how regular they are, when your period tends to occur, etc. Over the first two months, Oura will get to know your personal temperature rhythms and start to make predictions based on the patterns it sees as they happen. Each cycle, your feedback on your period start date and flow level helps predictions become even more accurate. 

Why Temperature? 

Period Prediction Beta gets to know your personal temperature rhythm because body temperature reveals key clues about menstrual cycle phases as your temperature naturally shifts along with your hormones: 

  • Your temperature is cooler during the first half of your cycle (your follicular phase, the phase where the follicles on your ovaries grow) when your estrogen levels are high.
  • Your temperature is warmer during the second half of your cycle (your luteal phase, the phase which begins with ovulation and the follicle turning into a corpus luteum) when your progesterone levels are high. 
  • Your temperature decreases at the start of your period when your hormone levels drop off.

How To Use This Feature

Follow the steps below:

1. Turn on Period Prediction Beta by opting in via the prompt on your Home screen (left) or finding the feature in the “hamburger” menu within settings (right). 

2. Read through details on how Period Prediction Beta works.

3. Answer a few simple questions to teach Oura about your past cycles.

4. Oura will get to know your personal temperature rhythms over the next two months and will start making predictions about your period. You can find a 3-day window for your expected period start date in the calendar view (left) and expect to receive notifications 6 days and 1 day before your expected start date.

5. At any time you can also log your period via the + button, then “Log period start.”

Common Questions 

What is the calendar method and how is Period Prediction Beta different? 

Historically, most period tracking solutions rely on “the calendar method” – marking the same day on your calendar each month and assume that your period start date will never change (e.g., if you’ve said your cycle is 30 days long, it will mark your period start every 30 days). In reality, periods change from cycle to cycle and variables like stress, diet, and illness can shift the day when your period arrives. That’s why Period Prediction Beta reads signals from your body as they happen so your predictions can update as your body changes, rather than relying on a date on the calendar that isn’t connected to the changes in your body.

When does Period Prediction Beta use the calendar method vs. temperature? 

Oura uses the first 60 days of your temperature data to learn what a typical cycle looks like for you. During those 60 days, Oura will base your predictions off of the calendar method and the questions you answered about your cycle during onboarding. After those 60 days, Oura will create smart predictions based on your temperature data for every cycle. Oura will only return to the calendar method if you’re missing enough nights of temperature data that Oura cannot detect your cycle pattern.

Can I use Period Prediction Beta if I’m on birth control or become pregnant? 

Period Prediction Beta is designed to work for individuals who have natural temperature patterns in their cycle because it uses the rise and fall of your temperature to detect different phases of your cycle. Hormonal contraceptives (e.g., birth control pills), pregnancy, or hormone replacement therapies hide or alter these patterns, preventing Period Prediction Beta from accurately predicting your period. If any of these use cases apply to you, we recommend leaving the beta. 

You can see an example below of an Oura user who has a natural temperature cycle and then goes on birth control, eliminating the patterns that Period Prediction Beta needs to accurately predict their period.

Where can I learn more about how my body changes across the menstrual cycle? 

Check out how to use the Temperature Trend view to spot patterns in your cycle or read about the changes across your entire body. 



[1] Creinin, M. D., Keverline, S., & Meyn, L. A. (2004). How regular is regular? An analysis of menstrual cycle regularity. Contraception, 70(4), 289-292.