Question

Explain the four phases of menstrual cycle detailly.​

Answer 1

Answer:

There are four phases: menstruation, the follicular phase, ovulation and

the luteal phase.

Explanation:

Menstruation:

Menstruation is the elimination of the internal lining of the uterine wall along with other secretions from the body through the vagina.

It usually lasts three to seven days but this could change to more or less days from month to month and depending on each woman.

The follicular phase:

The follicular phase starts on the first day of menstruation and ends with ovulation. During this phase the pituitary gland (situated at the

base of the brain) releases a follicle (cyst) stimulating hormone. This hormone produces 10 to 20 follicles in the ovary and each follicle

houses an immature egg. These follicles produce the hormone estrogen, which in turn thickens the lining of the endometrium in preparation to receive a fertilized egg. Often, only one follicle keeps growing and travels to the ovarian surface while the remaining follicles gradually fade and are absorbed back into the body.

Ovulation:

Ovulation occurs 12 to 16 days before the following period but not necessarily in the middle of the cycle. The term “ovulation” indicates the formation of a mature egg by one of the ovaries. The release of estrogen during the follicular phase causes the brain to produce a gonadotrophin-releasing hormone that prompts the pituitary gland to produce raised levels of luteinising hormone (luteotropic hormone). This extracts the mature egg from the follicle (cyst) and transports it from the ovary to the fallopian tube. If fertilization does not occur during this phase, the egg continues to the uterus and dissolves within 6 to 24 hours.

The luteal phase:

During this phase, the follicle from which the mature egg burst out (now called the yellow body of the ovary or corpus luteum) released a large quantity of progesterone and some estrogen. The two hormones help thicken the lining of the endometrium and maintain its thickness. If fertilization does not occur, the yellow

body degrades and progesterone levels decrease, leaving the lining unstable. The lining then falls away and a new menstrual cycle period begins.