The NICHD conducts and supports a range of research activities to learn more about causes, risk factors, and treatments for endometriosis. Short descriptions of this research follow below.
Institute Activities and Advances
Extramural Research on Endometriosis
The Institute supports research on endometriosis mostly through its Fertility and Infertility (FI) Branch, but also through other extramural organizational units. Findings from recent research efforts include (but are not limited to) the following:
Intramural Research on Endometriosis
Division of Epidemiology, Statistics, and Prevention Research (DESPR)
DESPR researchers study many different aspects of endometriosis. Among these efforts are the following:
- The Epidemiology Branch is conducting the Endometriosis Natural History, Diagnosis, and Outcomes Study. This study is examining the health of women from geographic areas with known environmental contamination who were undergoing laparoscopy to assess the relation between exposure to persistent environmental chemicals and the incidence and severity of endometriosis.
- Recently published findings from the study suggest that current statistics may greatly underestimate the number of women who have endometriosis. Among women seeking clinical care for endometriosis and a matched population cohort, endometriosis incidence ranged by two orders of magnitude by diagnostic method: 0.7% for histology only, 7% for MRI only, and 41% for visualized disease. The incidence of MRI-diagnosed endometriosis was 11% in the population cohort. Conservatively, then, 11% of women have undiagnosed endometriosis at the population level. These findings have implications for the design and interpretation of etiologic research, but also for the economic and overall health of the nation. (Source: Buck Louis, G. M., et al. (2011). Fertility and Sterility, 96, 360-365. PMID: 2171900.)
- Epidemiology Branch researchers are also studying the origins of endometriosis, including very early origins that might start in the womb. Visit Endometriosis Risk Might Begin Early for more information on this research.
Division of Intramural Research (DIR)
Currently, several Program in Reproductive and Adult Endocrinology (PRAE) components within the DIR are studying different features of endometriosis and its treatment. Some of these efforts include the following:
- Recent findings from PRAE researchers found that women with endometriosis had a higher prevalence of recurrent upper respiratory or vaginal infections, melanoma, and ovarian cancer than the general population. (Source: Gemmill, J. A., et al. (2010). Fertility and Sterility, 94, 1627-1631. PMID: 19945097)
- PRAE researchers are also working to treat the symptoms of endometriosis more effectively. In one study, researchers examined women with chronic pelvic pain and endometriosis. They found that lesion depth, disease severity (burden), and the number of lesions were not associated with pain location. Only painful urination (dysuria) and midline abdominal pain were associated with location of superficial endometriosis lesions. (Source: Hsu, A. L., et al. (2011). Obstetrics and Gynecology, 118(2 Pt 1), 223-230. PMID: 21775836)
- In a clinical study from the PRAE, researchers found that daily doses of raloxifene (a hormone-like drug) given after surgery for endometriosis was less effective at reducing pain than was surgery alone. They also found that raloxifene actually shortened the time to return of chronic pain. Because recurrence of endometriosis lesions did not correlate with return of pain, other factors such as estrogen are implicated in pelvic pain. The results of this study could lead to other advances in treating pain related to endometriosis. (Source: Stratton, P., et al. (2008). Obstetrics and Gynecology, 111, 88-96. PMID: 18165396)
- Investigators also found that women with endometriosis have reduced expression of four biomarkers of implantation compared to healthy controls. The investigators suggest this might indicate impaired endometrial receptivity in patients with endometriosis. (Source: Wei, Q. (2009). Fertility and Sterility, 91(5), 1686-1691. PMID: 18672236)
Other Activities and Advances
- The Specialized Cooperative Centers Program in Reproduction and Infertility Research (SCCPIR) is a national network of research-based centers, supported by the FI Branch, that aims to promote interactions between basic and clinical scientists with the goal of improving reproductive health.
- Through the SCCPIR, the NICHD also supports the Endometrium Database Resource, housed at Baylor College of Medicine. Its purpose is to curate genes reported in the literature to be regulated in the uterus in human, mouse, rat, cow, guinea pig, pig, and sheep. The Resource supplies tools that allow easy comparison of relative RNA expression from different experimental conditions in curated publications to determine how those conditions affect gene expression in various layers of the uterus.
- The FI Branch-supported Reproductive Medicine Network (RMN) studies issues related to infertility and reproductive health in women. Several RMN studies are examining the effectiveness of assisted reproductive technology, such as IVF, in promoting pregnancy among women who are infertile, including those who have endometriosis-related infertility.
- Researchers in the NICHD's Division of Intramural Research are currently conducting a clinical trial related to treatment for endometriosis-related pain. Visit Botulinum Toxin as a Possible Treatment for Endometriosis-Associated Pain for details.