The severity and frequency distribution of endometriosis subtypes at different ages: a model to understand the natural history of endometriosis based on single centre/single surgeon data

Abstract

Background and Objective: to study the natural history of endometriosis. Materials and methods: the analysis of all women (n=2086) undergoing laparoscopy for pelvic pain and endometriosis between 1988 and 2011 at University Hospital Gasthuisberg. Main outcome measures: the severity of subtle, typical, cystic and deep endometriosis in adult women, with or without a pregnancy, as estimated by their pelvic area and their volume. Results: the number of women undergoing a laparoscopy increased up to 28 years of age and decreased thereafter. Between 24 and 44 years, the severity and relative frequencies of subtle, typical, cystic and deep lesions did not vary significantly. The number of women younger than 20 years was too small to ascertain the impression of less severe lesions. The severity of endometriosis lesions was not less in women with 1 or more previous pregnancies or with previous surgery. There was no bias over time since the type and severity of endometriosis lesions remained constant between 1988 and 2011. Conclusions: severity of endometriosis does not increase between 24 and 44 years of age, suggesting that growth is limited by intrinsic or extrinsic factors. Severity was not lower in women with a previous pregnancy. What is new: considering the time needed for lesions to become symptomatic together with the diagnostic delay, the decreasing number of laparoscopies after age 28 is compatible with a progressively declining risk of initiating endometriosis lesions after menarche, the remaining women being progessively less susceptible.

Pathogenesis Based Diagnosis and Treatment of Endometriosis

“…The risk of initiating endometriosis lesions varies with the genetic predisposition and with the oxidative stress from retrograde menstruation and the pelvic microbiome. It is attractive to consider that in susceptible women this risk is highest after puberty and after initiating sexual activity ( 58 ), i.e. during or early after puberty.…”

“…It is widely believed that medical therapy prevents the growth of endometriosis. Our recent observation that endometriosis is a self-limiting disease since the severity of endometriosis lesions does not vary with age or with previous pregnancies challenges this concept (91).…”

“…Most subtle lesions disappear spontaneously and can be considered normal endometrium in an abnormal location. The natural history of typical, cystic and deep endometriosis lesions seems self-limiting since the variability of their severity does not increase with age ( Figure 2 ) ( 58 ). After a period of growth, lesions stop growing and become inactive, probably because of fibrosis, because of the immunologic reaction and the repetitive trauma and repair of bleeding.…”

“…The least-square regression analysis with 95% confidence limits indicate women without children. In the insert, the boxplots of women with 0, 1 or >1 children demonstrated the absence of a difference between the 3 groups ( 58 ).…”

“…It is therefore logical, as supported by data, that susceptible women will have the highest risk of developing endometriosis early in life, and that the risk will decrease progressively in the remaining group. After age 30, the risk of initiating endometriosis becomes small ( 58 ).…”