ABSTRACT
Endometriosis affects 6-11% of premenopausal women, causing pain, infertility, and
billions of dollars in U.S. health care related costs annually. With a poorly understood
etiology, endometriosis is characterized by hormonally responsive endometrial implants
outside the uterus. Evidence from experimental and human studies indicate that
endocrine disrupting chemicals, to which humans are nearly ubiquitously exposed, may
play a role in endometriosis etiology and severity. We propose to measure nine
perfluoroalkyl substances (PFASs) and 53 persistent organic pollutants (POPs) to which
the population is broadly exposed, in eutopic (healthy uterine tissue) and ectopic
(endometriosis implants) endometrial tissue. The literature is limited in that there are no
studies of endometriosis incidence and severity in relation to PFASs, POPs, and their
mixtures measured in uterine tissue. This study leverages a unique biorepository
collected from the operative cohort of the Endometriosis: Natural History, Diagnosis,
and Outcomes (ENDO) Study, an NICHD study which enrolled 495 women aged 18-44
from 14 clinical centers in California and Utah prior to laparoscopic surgery. We will
determine: 1) whether higher levels of PFASs, POPs, and their mixtures in eutopic
endometrial tissue are associated with incident endometriosis and 2) how these
exposures in ectopic endometrial tissue are associated with endometriosis severity; 3)
whether mixtures of PFASs and POPs across serum, adipose tissue, and eutopic
endometrial tissue, are associated with endometriosis incidence; and finally, 4)
recognizing the infeasibility of most epidemiologic studies of gynecologic disease to
obtain endometrial tissue, we will develop a model to predict eutopic endometrial dose
from serum levels of PFAS and POP exposure. This study will provide critical data on
PFASs and POPs, which will advance scientific understanding and inform policy
makers.