Menstrual cycle is the process of physiological changes that occur in fertile women and other female primates for the purpose of sexual reproduction.
- It is a monthly cycle.
- It composed of blood , destroy part of endometrium , mucous & water.
- It is the way the uterus changes before & after the egg cell is released.
- Average menstrual cycle is 28 days from the start of one to the next.
- Menarche (starting of first menstruation) occurs usually between 11-14 years age.
- Menophase (end of menstrual cycle) occurs usually 45-50 years of age.
PHASES OF MENSTRUATION
It begins with the first days & lasts till the 5 days of menstruation cycle.
Uterus sheds with its inner lining of soft tissue & blood vessels exits from vagina in the form of menstrual fluid.
Begins on the 1 st day and lasts till the 13th day of menstruation cycle.
In this phase egg cells starting grow in size then begin to mature in a sac-like follicle, which secrets estrogens hormone that stimulates the uterus to develop endometrium.
On the 14th day of cycle, pituitary gland secrets LH hormone that causes the ovary to release the matured egg cell
Begins on the 15th day & lasts till the end of the cycle.
Egg cell released that stays in Fallopian tube for 24 hours, if a sperms can’t impregnate the egg within this time the egg cell destroys
Hormone which causes the uterus to retain its endometrium gets used up by the end of the menstrual cycle.
HORMONAL REGULATION IN MENSTRUAL CYCLE
There are mainly four hormones which regulates the menstrual cycle.
Follicle stimulating hormone which is secreted from anterior pituitary.
It helps in secretion of estrogen hormone for development of follicles. It mainly helps in the growth of follicle.
Secreted from the ovaries.
It stimulates the LH (luteinizing hormone) secretion and inhibits LH and FSH secretion.
Secreted from the anterior pituitary.
It helps in the development of corpus luteum and stimulates the progesterone secretion.
Secreted from the corpus luteum.
Inhibits the secretion of LH and FSH.
This is the general notes on menstrual cycle and its hormonal regulation.
Thank you for reading.