Q.If the menstruation cycle does not begin at puberty, the condition is called

The First Menstrual Period

The first menstrual period, called menarche, marks the point at which a girl's body reaches sexual maturity — the beginning of puberty's reproductive changes becoming visible. It is not an illness and nothing to be ashamed of; it is simply a biological signal that the body has reached a new stage of development.

What Actually Happens

Every cycle, the uterus builds a soft, blood-rich lining to prepare for a possible pregnancy. If no pregnancy occurs, the body sheds this lining — menarche is the first time this shedding happens. It typically occurs somewhere in the range of 8 to 15 years of age, and the exact age varies considerably from one girl to another depending on genetics, nutrition, and overall health.

The bleeding itself usually lasts around 3 to 5 days, and a woman continues to menstruate from puberty until menopause, roughly ages 45–55 (menopause typically arrives around age 50). A normal menstrual cycle — the gap from the start of one period to the start of the next — falls between 21 and 35 days; a cycle shorter than 21 days or longer than 35 days is considered outside the normal range and worth medical attention.

Why It Matters

Menstruation is a sign of reproductive health, and understanding what is normal for one's own body is the first step to noticing when something needs medical attention — for example, periods that stop for several months, periods that are extremely painful, or bleeding that is unusually heavy. …