Background: Endometriosis is a well-known cause of infertility, and the anti-Mullerian hormone (AMH) is an
accepted biomarker of ovarian reserve and response to artificial reproductive technology procedures. The present
study was a prospective analysis of age-dependent AMH serum concentration in women with bilateral and
unilateral ovarian endometriomas before therapy onset compared with healthy controls.
Methods: This prospective cross-sectional study included 384 women aged 18–48 years. AMH serum concentration
was assessed between days 3 and 6 of the menstrual cycle in 78 patients with bilateral and 157 patients with
unilateral ovarian endometriomas and compared with 149 healthy controls. Ovarian endometriosis was confirmed
histopathologically, and data were presented as medians with interquartile range (IQR).
Results: Stage III endometriosis was diagnosed in 53.2 %, stage IV in 18.3 %, stage V in 23.4 % and stage VI in 5.4 %
of the patients. Patients with bilateral ovarian endometriomas showed the lowest median AMH levels compared
with patients suffering from unilateral ovarian endometriosis (0.55; IQR: 0.59 vs. 2.00; IQR: 2.80; p < 0.001) and the
control group (0.55; IQR: 0.59 vs. 2.84; IQR: 3.2; p < 0.001). Median AMH concentration values were not significantly
different between patients with unilateral ovarian endometriosis and the healthy controls (2.00; IQR: 2.80 vs. 2.84;
IQR: 3.2; p = 0.182). A strongly negative correlation between AMH levels and age was confirmed in healthy
individuals (R = −0.834; p < 0.001) and women with unilateral ovarian endometriomas (R = −0.774; p < 0.001).
Patients with bilateral ovarian endometriosis showed a significantly negative but only moderate correlation
between AMH levels and age (R = −0.633; p < 0.001), which was significantly lower than in the healthy controls
(R = −0.633 vs. R = −0.834; p = 0.006) but not in the patients with unilateral ovarian endometriosis (R = −0.663 vs.
R-0.774; p = 0.093). Based on a multivariate regression analysis, only bilateral localization of ovarian endometrial
cysts (p = 0.003) and patient age (p < 0.001), but not left/right localization of unilateral cyst or cyst volume, were
negatively associated with AMH serum concentration.
Conclusion: According to our data, unilateral ovarian endometriosis had a moderately negative and nonsignificant
effect on AMH-based ovarian reserve evaluated prior to surgery, irrespective of age. In contrast, the ovarian reserve
was significantly reduced in women with bilateral ovarian endometriomas