Female Menstrual Cycle (Grade 10)

Página 1

female menstrual cycle What is it?

From puberty until menopause, the female reproductive system normally goes through a series of cyclic changes

Each cycle lasts about an average of 28 days and is called a menstrual cycle.

They are divided into 4 stages

MEstage 1: menstruation stage (Days 1-5)

the blood lining of the uterus breaks down, resulting in bleeding which are expelled through vagina

This stage lasts 5-7 days, experience variety of sensations - backache, headaches, cramping, breast tenderness

stage 2: follicular stage (Days 6-13)

Several eggs mature within a follicle

follicle manufacture and secrete oestrogen

rise in oestrogen result in lining thickening of uterus.

follicle moves to the surface of the ovary

stage 3: ovulation stage (days 13-14)

Shortest Phase in the cycle

Release of egg from the ruptured follicle

Ovum is in fallopian tube where it awaits fertilisation

egg can survive to 6-24 hours

Cervix secretes clear fertile mucous that assists sperm survival

stage 4: luteal stage (days 15-28)

If fertilisation occurs:

- ruptured follicle becomes corpus luteum - which travels back to ovary to secrete progesterone

this results in thickening of uterus lining to prepare the uterus to receive the embryo

progesterone at peak on days 19-22

If no fertilisation occurs - uterus lining becomes loose and process starts ageain