The Menstrual Cycle Flashcards
What is the menstrual cycle?
A recurring process in which the lining of the uterus (womb) is prepared for pregnancy, and if pregnancy does not happen, the lining is SHED at MENSTRUATION.
What are the two main functions of oestrogen?
- The initial repair and build up of the uterus wall
- Stimulates ovulation (release of the egg from the ovary)
What is the hormone PROGESTERONE’s role?
To build up and maintain the think lining of the uterus and help the development of the placenta of implantation (embryo attaching to uterus lining) occurs.
In terms of oestrogen and progesterone levels, what happens if pregnancy doesn’t occur?
The levels drop towards the end of the cycle and this causes MENSTRUATION to occur.
Why do both hormones not peak at the same time?
To maintain the thick uterus lining.
When does menstruation occur? What are the hormone levels like? What happens?
Mensturation takes place between days 1-5.
The blood flows out of the vagina as the lining of the uterus break up.
There are low levels of oestrogen and progesterone.
What happens between days 6-10? What are the hormone levels like?
The lining of the uterus starts to grow again. The levels of oestrogen and progesterone start to increase.
What happens between days 11-17?
The sperm left in vagina during this time will still be alive when the egg is released. During this time the sperm in the OVIDUCTS is likely to cause FERTILISATION.
What process takes place during days 13-15? What are the hormone levels like?
Ovulation takes place.
An egg is released from the OVARY.
The OESTROGEN level PEAKS.
What happens between day 18-28?
If the egg is not fertilised it dies and eventually passes out of the vagina.
The oestrogen and progesterone levels DROP.
What hormone is necessary for ovulation?
Oestrogen!
The lining of the uterus builds back up between days 4-14, what event must occur to prevent the lining breaking down again?
Fertilisation!
During what time would a female be most fertile?
From days 13-17: think uterus lining - egg will have been released.
During what time would a woman be least fertile?
From days 1-5: Thin uterus lining - hormone levels are too low.
The uterus lining built up after day 5 or 6 will last until when?
Around day 16.
