Question

How do menstruation start in girls​

Answer 1

Explanation:

Menstruation is the elimination of the thickened lining of the uterus (endometrium) from the body through the vagina. Menstrual fluid contains blood, cells from the lining of the uterus (endometrial cells) and mucus. The average length of a period is between three days and one week.

Answer 2

it starts naturally after attaining the age of 12 to 14 years and end at the age of about 45 years old