Preface

Endometriosis is a prevalent disease affecting up to 10 percent of reproductive-age women globally. While we have made great strides towards our understanding of the pathophysiology of endometriosis, much is still unknown. We do know that endometriosis is estrogen-dependent and is mediated by immunologic factors. Defined as the presence of endometrial glands and stroma outside of the uterus, women may have debilitating symptoms including pain and infertility or the disease can be diagnosed incidentally at the time of pelvic surgery, making a determination of true prevalence particularly challenging.

In this book, we explore risk factors for endometriosis including environmental factors that are shedding light on this disease. We also investigate novel methods for diagnosing and treating pain related to endometriosis, which can be debilitating in some women. Conditions associated with endometriosis including adenomyosis, invasion of endometrial glands and stroma into the uterine muscle, and infertility are reviewed in depth. Finally, we look at treatment options for women with endometriosis ranging from hormonal to surgical. Together, we provide a comprehensive look at the diagnosis, treatment and risk of endometriosis to better inform practitioners in caring for patients with endometriosis.

**II**

**Section 5**

Interventional Treatment of Endometriosis

*by Yang Xiaomin, Han Jun, Feng Pin and Yang Xiaojun*

Endometriosis Treatment **103**

**Chapter 7 105**

**Courtney Marsh** University of Kansas Medical Center, United States of America

**1**

Section 1

Epidemiology of

Endometriosis:

Risk Factors and

Environmental

Contribution

Section 1

Epidemiology of Endometriosis: Risk Factors and Environmental Contribution

**3**

**Chapter 1**

**Abstract**

metriosis remains weak.

estrogenic

**1. Introduction**

The Link between Environmental

Endometriosis is widely acknowledged to be an estrogen dependent disease or unknown etiology. Recognition that environmental toxicants can bind with and activate the estrogen receptor, dysregulate steroid metabolism and, in some cases, act as anti-androgenic substances (phthalate esters) has led to proposal that exposure to environmental toxicants are associated with increased risk of endometriosis. Since our last review of the subject in 2008, the literature has expanded with several epidemiological and biomonitoring studies suggesting a potential association, whereas others have been unable to demonstrate a link between exposure and enhanced risk. Therefore, we carried out a systematic review and critical appraisal of the literature published over the past decade (2009–2019). The majority of studies found dealt with exposure to polychlorinated biphenyls (PCBs), dioxins, dioxin-like and non-dioxin-like compounds, bisphenol A and phthalate esters. Several studies suggest a potential association between exposure to environmental toxicants; however, important weaknesses in study design, methodology, and analysis together with many contradictory studies weaken confidence in these associations. Consequently, we conclude that despite a growing literature, evidence for an association between exposure to environmental toxicants and risk of endo-

**Keywords:** endometriosis, endocrine disrupters, phthalates, bisphenol A, dioxin,

Endometriosis an estrogen dependent disease characterized by ectopic growth of endometrial glands and stroma outside of the uterine cavity. It is estimated that endometriosis may affect anywhere from 5 to 45% of all women [1]. Although retrograde menstruation has become the most widely accepted theory for the development of endometriosis [2], it cannot account for endometriosis in distant organs

While the cause of endometriosis remains unknown, it most likely arises from a multifaceted origin involving the interaction of environment and genetics [3]. Among the different hypotheses advanced, a growing body of literature suggests that environmental factors including environmental toxicants may play a role in the pathophysiology of endometriosis. Lifestyle and medication use point to

such as the lung and brain. Therefore, alternative explanations are sought.

Toxicant Exposure and

*Shay M. Freger and Warren G. Foster*

Endometriosis Re-Examined
