Impact on Quality of Life of "Endo-App" (ELEA)

Inclusion Criteria: Legal capacity * Living in Germany * Adequate german language skills * Female biological gender * Ages eligible for study ≥ 18 years * Medical Diagnosis of endometriosis Diagnosis verification by following documents: 1. Operation Report 2. Histological finding 3. MRI finding 4. Other medical examination documents with endometriosis diagnosis (for example sonography, colonoscopy, cystoscopy) Owning a smartphone and having an internet access Willingness and capability of using the smartphone device and the Endo App Motivation to regularly fill out the questionnaries Owning an e-mail address for App registration Absence of exlusion criteria Exclusion Criteria: * Absence of inclusion criteria * Pregnancy existing at survey period * Ongoing hormonal fertility treatment or planned treatment within the next 12 weeks (artificial insemination as part of in vitro fertilization, such as IVF or ICSI, hormone injections for fertility treatment) * Ongoing or within the next 12 weeks planned rehabilitation or multimodal pain therapy * Planned change in hormone therapy (change of active substance, new start or discontinuation of therapy) in the next 12 weeks or change in hormone therapy within the last 8 weeks before the start of the study * Endometriosis surgery planned in the next 12 weeks or endometriosis surgery performed within the last 8 weeks prior to study start * Previous or existing access to Endo app or current prescription