53. What is the menstrual?
Although the reproductive organs are present in the body from birth,
they do not function until sexual maturity is attained.
In India, a female (girl) attains it at the age of 10-11 years. In female,
when she starts producing eggs, a series of changes take place, this is
called the menstrual cycle. The cycle takes about four weeks.
During the first two weeks, an egg develops in an ovary and is
released into the womb. The menstrual cycle is controlled by a centre
in the brain called the hypothalamus, which acts as a menstrual
clock. The pituitary glands release several hormones. One hormone
stimulates the growth and maturation of the egg in the ovary.
Another hormone stimulates the release of these ripened eggs. If the
egg is fertilized by a sperm, it will be nourished by secretions from
the cells lining the womb. If the egg is not fertilized, the unfertilized
egg and the remains of the womb lining are expelled together ll I
with some blood. This process is called menstruation and it lasts for
about five days. Menstruation continues until the age of about 50
years.
