How Long Is a Normal Menstrual Cycle?

Question

Accepted Answer

A normal menstrual cycle lasts between 21 to 35 days, with 28 days being the average. A cycle is counted from the first day of one period to the first day of the next. The period itself typically lasts 2 to 7 days, with the heaviest flow usually occurring in the first two days. It is normal for cycle length to vary by a few days each month. A cycle is considered irregular if it is consistently shorter than 21 days or longer than 35 days. You should see a doctor if your periods regularly fall outside this range, last more than 7 days, involve extremely heavy bleeding, or if you notice a sudden change in your usual pattern.