Phendo Challenge #2 Results

Citizen Endo
4 min readMay 4, 2018

For our latest Phendo tracking challenge (from March 20-March 27, 2018), we invited participants to complete the World Endometriosis Research Foundation (WERF) Clinical Questionnaire as well as a questionnaire about the type and stage of their endometriosis. This survey represents the gold standard in clinical questionnaires for endometriosis.

Every woman has their own experience with endometriosis, and their clinical history of the disease. By using the WERF survey we can standardize this information and begin to learn about endometriosis across patient experiences. Moreover we can use this information to evaluate the results of what we learn from Phendo data. Ultimately, we hope to use Phendo data to inform our understanding of different types of endometriosis. While the WERF survey is important in characterizing clinical history of the disease, Phendo data provides us with a more granular and nuanced view of signs and symptoms over time. This longitudinal view of the disease is important for better understanding how the disease might vary with the hormonal cycle and the impact of symptoms on day-to-day life.

Because of all of your efforts in responding to our challenge, we wanted to be sure to share some of the results with you! Overall 34 users completed the WERF survey during the challenge period, and our participants ranged in age from 19–47.

Pain During Periods

Painful periods are a very typical symptom of endometriosis, and we wrote previously about how endometriosis-related pain impacts women’s work, relationships, and quality of life significantly.

Notably, 45–95% of all menstruating women experience painful periods, and 10–25% of women without endometriosis experience severe period pain. 85% of our participants (N = 34) reported severe cramps during their periods, 70% (N = 27) noted that this pain prevents them from completing daily activities.

Delay in Diagnosis

Many women may suffer from endometriosis for years before they receive a diagnosis. For many women, diagnoses can offer validation as well as greater access to treatment. Recent research shows that women in the U.S. wait an average of 4.4 years from symptom onset to diagnosis, while women in the U.K. wait an average of 8 years.

Moveover, women consult an average of 3 physicians before receiving an endometriosis diagnosis. Over 73% of our participants reported consulting at least 3 physicians before they were diagnosed, with 60% seeing at least 5 physicians.


Unfortunately, a diagnosis does not guarantee quick relief.

Even when women have surgery for endometriosis, pain recurs in 20–40% of cases, and 15–20% of women undergo further surgeries. 86% of our participants (N = 28) have had at least one surgical procedure for endometriosis, with 36% having had multiple procedures.


Women with endometriosis report high levels of anxiety and depression — conditions which may enhance their experience of pain. 48% (N = 33) of our participants reported having depression or other mood disorders requiring medication or therapy, while 39% noted an anxiety disorder. Women with endometriosis are also more likely to suffer from migraines, and we had 27% (N = 33) of our participants report having migraines.

Genetics & Family History

Research suggests that genes play an important role in endometriosis. Specifically, large-scale twin studies show that ~50% of endometriosis variation is attributable to genetic factors.

32% (N = 34) of our participants reported a relative (mom, sister, aunt, cousin, or grandma) with endometriosis.

Finally, thank you to all of our participants! It’s great that we were able to get 34 more responses to the WERF questionnaire. However we need far more responses in order to help us better understand endometriosis. If you are a Phendo user and haven’t already filled out the WERF questionnaire, please go the Profile tab in Phendo and click on ‘Medical History’ to complete the survey.

You can sign up to participate in Citizen Endo challenges by downloading Phendo and going to the Citizen tab in the Phendo app.

Download Phendo for iOS here.

Download Phendo for Android here.

For more information about our research and Phendo visit

You can find answers to frequently asked questions about Phendo at

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Citizen Endo

Patients and data science for an endometriosis cure: We bridge the gap between patient experience and clinical characterization of endometriosis.