AMH and endometriosis: Similarly, it has been reported that AMH levels are lower in patients with stage III/IV endometriosis without prior ovarian surgery than in controls (0.97 ± 0.59 ng/mL in the study group [mean age, 33.6 ± 1.9 years] vs. 1.72 ± 0.63 ng/mL in the control group [mean age, 32.6 ± 2.0 years], mean ± SD; P = 0.001) [21].