Vol 91, No 4 (2020)
Research paper
Published online: 2020-04-29

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Increased risk of endometriosis in patients with endometritis — a nationwide cohort study involving 84,150 individuals

Kent Yu-Hsien Lin1, Cherry Yin-Yi Chang23, Wu-Chou Lin34, Lei Wan345
Pubmed: 32374019
Ginekol Pol 2020;91(4):193-200.


Objectives: To evaluate the incidence of endometriosis among endometritis patients and its association with confounding
Material and methods: A population-based, retrospective cohort study of women aged between 20 to 55 years, who were
newly diagnosed with endometritis between 2000 to 2013. A total of 16,830 endometritis patients and 67,230 non-endometritis
individuals were enrolled by accessing data from the National Health Insurance Research Database of Taiwan.
The comorbidities accessed were uterine leiomyoma, rheumatoid arthritis, ovarian cancer, infertility and allergic diseases.
Results: The mean follow-up period was 9.15 years for the non-endometritis cohort and 9.13 years for the endometritis
cohort. There were significantly higher percentages of uterine leiomyoma, rheumatoid arthritis, infertility, ovarian cancer
and allergic diseases in the endometritis cohort than in the non-endometritis cohort. Patients with endometritis had
a 1.5-fold increased risk of their condition advancing to endometriosis (HR 1.58, 95% CI 1.48–1.68).
Conclusions: Our results suggest that patients with endometritis exhibited a positive correlation in developing endometriosis.

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