GSTM1 and adenomyosis: After adjustment using multiple logistic regression analysis, adenomyosis was correlated with Hb concentration (or = 0.971, 95% CI 0.954–0.988, p < 0.001), PC (or = 1.006, 95% CI 1.002–1.011, p = 0.004), PT (or = 3.878, 95% CI 2.347–6.409, p < 0.001), age (or = 1.062, 95% CI 1.013–1.114, p = 0.013), and uterine size (or = 1.103, 95% CI 1.011–1.203, p = 0.028).