Final answer:
Asherman's syndrome is the uterine disorder most directly associated with causing amenorrhea, as it involves the formation of adhesions within the uterine cavity. While endometriosis and uterine fibroids can cause other menstrual issues, they don't typically lead to amenorrhea. PCOS, primarily an ovarian disorder, can also cause irregular or absent menstruation.
Step-by-step explanation:
Uterine Disorders that Cause Amenorrhea. Among the uterine disorders that can cause amenorrhea, Asherman's syndrome is specifically associated with this condition. Asherman's syndrome involves the formation of adhesions or scar tissue in the uterine cavity, often as a result of surgery or infection, and can lead to amenorrhea as well as infertility. While uterine fibroids may cause various symptoms, such as heavy menstrual bleeding and pelvic pain, they do not typically cause amenorrhea unless they alter the uterine lining significantly. Endometriosis is a condition where tissue similar to the lining of the uterus, the endometrium, grows outside it, which can lead to infertility. However, it does not characteristically cause amenorrhea. Indeed, endometriosis often leads to heavier periods and can cause painful menstruation.
Finally, Polycystic ovary syndrome (PCOS) is an endocrine disorder that can lead to anovulation and can cause irregular or absent menstruation, thus potentially resulting in amenorrhea. While PCOS is primarily related to ovarian function, it can have indirect effects on the uterus.
In summary, Asherman's syndrome is the uterine disorder most directly associated with causing amenorrhea among the options given.