What Is a Normal Period? A normal period (or normal menstruation) is different for every woman. Each month, one of your ovaries releases an egg. Meanwhile, your uterus gets ready to help your baby grow if that egg gets fertilized. If it does, you’re pregnant. If it doesn’t, your body sheds the lining of your uterus through your vagina. That’s your period. It happens, on average, every 28 days. Think about how old you were when you got your first period. Now think about how old you may be when you enter menopause. Your body and life will change a lot from one to the other, right? So does your menstrual cycle. When it comes to periods, "normal" covers a lot of ground. Use the broad range of factors below as a guide. And remember: The only true normal is what's normal for you.