I don't know anyone who's thrilled to have her monthly visitor. The bloating, mood swings, and insane sugar cravings are far from a good time. Whether you like it or not though, getting your period is actually a good indication that your body is functioning as it should be. If your period stops, (and you're not preggers), it can be a big red flag that something is wrong. This condition is known as amenorrhea and it can be caused by depression, chronic illness, certain medications (like chemotherapy), or eating disorders. Fitness fanatics who exercise excessively may also notice Aunt Flo's disappearance. To learn more about this condition, known as athletic amenorrhea, take this little quiz.