A postmenopausal woman with vaginal bleeding has multiple potential evaluations. Which is the most reliable diagnostic evaluation for suspected endometrial pathology?

• A. Pap smear
• B. Endometrial biopsy
• C. Serum prolactin level
• D. Serum FSH and LH levels

Answer: (B)

When a postmenopausal woman presents with vaginal bleeding and there’s concern for endometrial pathology, obtaining tissue from the endometrium to examine under the microscope is the most reliable way to confirm what’s going on. An endometrial biopsy directly samples the lining of the uterus, allowing detection of hyperplasia, atypia, or cancer with histologic confirmation. A Pap smear looks at cervical cells and often misses endometrial disease, so it isn’t sufficient for diagnosing endometrial pathology. Hormonal tests like serum prolactin or FSH/LH don’t diagnose endometrial pathology and aren’t reliable for confirming cancer or hyperplasia; they’re more about hormonal status than tissue pathology.