Minimal and mild endometriosis: Is there anything new under the sun?

Research on endometriosis in patients with minimal or mild lesions is marred by our ignorance of the prevalence of limited stages in the asymptomatic female population of reproductive age. Laparoscopic studies performed on women undergoing tubal sterilization suggest that 2-8% are affected. However, the estimates may be unreliable because the studies were retrospective and misdiagnosis of subtle endometriosis cannot be excluded. In a recent prospective study of 86 asymptomatic women, more than 40% had minimal or mild lesions at laparoscopy. The data available do not support the suggestion that limited forms must always be treated to prevent disease progression, nor do they demonstrate worsening in all cases of minimal and mild endometriosis. Furthermore, there is no definitive evidence that the medical and surgical cytoreductive treatments available are effective in preventing eventual progression of the disease in some of the patients. We still do not know the prevalence of minimal and mild endometriosis in the healthy population, the percentage of progression towards severe stages or the risk factors of evolution of the disease. The hypothesis to test is that minimal endometriosis is partly a paraphysiologic condition that is frequently self-limited or resolves spontaneously.