It has been shown that when AMH < 1 ng/mL, the clinical pregnancy rate is generally low, and the pregnancy rate tends to increase as AMH increases.15 In addition, elevated FSH and LH, as well as reduced E2, all indicate a decline in ovarian reserve.16 Ovarian reserve can be declined due to endometriosis, chemotherapy and gynecological surgery, of which ovarian surgery is an important risk factor for causing a decline in ovarian reserve. Here, PLOD1 is linked to endometriosis.