Understanding Menstrual Cycles: How Periods Work

Females cannot make their periods come. Periods are a natural part of the menstrual cycle and the body's preparation for pregnancy. They occur when the lining of the uterus (called the endometrium) sheds if the egg is not fertilized. Periods typically arrive every 28 days, although this can vary from woman to woman. It is not possible to induce a period to come at a different time or make it arrive sooner.