What is the test?
In general, doctors take biopsies of areas that look abnormal and use them to detect cancer, precancerous cells, infections, and other conditions. For some biopsies, the doctor inserts a needle into the skin and draws out a sample; in other cases, tissue is removed during a surgical procedure.
This particular biopsy, endometrial biopsy, takes a tissue sample from the lining of your uterus (the endometrium). An endometrial biopsy is used to find 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.