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) 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 users on iOS and is coming soon for Android. 

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.”

What’s Next? 

Period Prediction Beta can help you find your personal cycle rhythm. You can also look for insights of your own using the Temperature Trend view to spot patterns in your cycle. 

As you learn more about your cycle, you can read more about Oura’s research into why and how cycles vary, learn how to use your Oura Temperature Trend view to track different phases of your cycle or see the latest related research with Oura: 

Available on iOS at launch. Android available in 2022


[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.