Abnormal bleeding refers to any bleeding that is unusual in amount, duration, or timing compared to a person's normal pattern. This can include heavy menstrual periods, bleeding between periods, or bleeding after menopause. It may also occur in other contexts, such as gastrointestinal bleeding or nosebleeds that happen frequently. Causes of abnormal bleeding can vary widely and may include hormonal imbalances, medications, or underlying health conditions like fibroids or polyps. It is important to consult a healthcare professional for proper evaluation and diagnosis if abnormal bleeding occurs, as it may indicate a more serious issue.