What is the test?
In general, a biopsy is a sample of tissue. This particular biopsy, endometrial biopsy, takes a tissue sample from the lining of your uterus (the endometrium). An endometrial biopsy is used most often to evaluate the possibility of endometrial cancer. Endometrial cancer might explain unexpected vaginal bleeding, particularly if bleeding occurs after menopause.
Often an ultrasound is used as a first test to check for endometrial cancer. The inner lining of the uterus looks like a "stripe" on an ultrasound, and it is normally a thin stripe. If a woman with unexpected vaginal bleeding has a thick stripe from the lining in the uterus, an endometrial biopsy may be used to check more specifically for cancer.