Cause of post-menopausal bleeding is :
**Core Concept**
Post-menopausal bleeding is a clinical presentation that occurs in women after menopause, typically defined as 12 months after the last menstrual period. The causes of post-menopausal bleeding are diverse and can be categorized into malignant and non-malignant etiologies. The most common malignant cause is endometrial cancer, while non-malignant causes include atrophy, polyps, and endometrial hyperplasia.
**Why the Correct Answer is Right**
The correct answer is **Endometrial Cancer**. Endometrial cancer is the most common malignant cause of post-menopausal bleeding, accounting for approximately 10% of cases. It arises from the endometrium, the lining of the uterus, due to unopposed estrogen stimulation, leading to unchecked cell growth and potential malignant transformation. The risk factors for endometrial cancer include obesity, unopposed estrogen therapy, and genetic mutations such as Lynch syndrome.
**Why Each Wrong Option is Incorrect**
**Option A:** Atrophy is a non-malignant cause of post-menopausal bleeding, but it is less common than endometrial cancer. Atrophy occurs due to the decrease in estrogen levels, leading to thinning and shrinkage of the endometrium.
**Option B:** Polyps are a common non-malignant cause of post-menopausal bleeding, but they are less likely to cause bleeding than endometrial cancer. Polyps are growths on the endometrium that can cause bleeding due to their irregular shape and size.
**Option C:** Endometrial hyperplasia is a non-malignant condition characterized by the overgrowth of the endometrium. While it can cause post-menopausal bleeding, it is less common than endometrial cancer.
**Clinical Pearl / High-Yield Fact**
The "Rule of 70" is a useful clinical guideline: if a post-menopausal woman is <70 years old, the likelihood of malignancy is 50%.
**Correct Answer:** C. Endometrial Cancer.