|Class 8 Biology Reaching the Age of Adolescence||Menstrual cycle in females|
Menstrual cycle in females
When girls reach the age of adolescence they enter into the age when they are capable of reproduction.
The reproductive age in girls begins right form the age of 10 to 12 years and ends at the age of 45 to 50 years.
At the onset of puberty, the ovaries in girls starts to mature. Every month one ovum gets matured and then gets released by the ovaries. This procedure happens once in 28 to 30 days approximately.
At this time of month the uterine wall becomes thick to receive the mature egg. If the egg gets fertilised and begins to develop it leads to pregnancy.
Fig. Steps involved in pregnancy
But if fertilisation does not occur then the released egg and thick lining of uterus along with blood gets shed off through the vagina in females.
This leads to bleeding in women at a specific period of month (once in about 28-30 days) and is called menstruation.
The first menstrual flow in girls once they reach the age of adolescence is called menarche.
The stoppage of menstrual flow at the age of 45-50 years in girls is called menopause.
The menstrual cycle includes following steps: