Implications for further research and treatment
There is a need to understand the consequences of affective symptoms on pain amplification or pain reduction during endometriosis treatment, which is very important in clinical practice. Chronic pelvic pain improvement alone does not automatically improve depressive symptoms and this assumption produces delays concerning psychosomatic care [97,98]. However, improvements in depression, anxiety and pain catastrophizing, can influence pain perception [99] and, therefore, improve quality of life as well as sexual and social functioning which in turn may reduce societal relevant health care costs [8,13]. Hence, an integrated and patient-centred approach to medical, psychological and sexual issues is suggested [51, 106]. Integration of care is deemed necessary at the hospital level and between hospital and primary care, and a multi-component strategy should include efforts to combat stigmatization concerning psychiatric comorbidity [100]. With regard to symptom formation (or in other words how symptoms impact on symptoms as in pain sensitization), the Experience Sampling Method (ESM) might be able to unravel how affective complaints and pain are related over time [107]. ESM is an ecological momentary assessment tool, which could help to provide information on symptoms in the context of daily life including psychological symptoms and sexuality [108]. This may help to overcome the limitations of current retrospective questionnaires [101].