What are the stages of the menstrual cycle in a human female, using diagrams and captions?

The cycle is divided into 4 phases/stages:

• Menstrual
• Follicular
• Ovulation
• Luteal

Here are the 4 phases (in order):

• MENSTRUAL PHASE

The menstrual cycle

begins

(day 1 is) from the start of

menstruation.

Menstruation takes place when there is no fertilisation, so the thick lining of the uterus breaks down.

The menstrual phase ends when menstruation ends.

Then the follicular phase begins.

• FOLLICULAR PHASE

In this phase, the

ovary gets its internal system ready

to release the egg.

The egg sits

inside a follicle

inside the ovary.

So the ovary develops the follicle so that the follicle becomes prepared to release the egg.

As the follicle develops, it gets bigger.

When the follicle reaches

full size

, the follicular stage ends.

Then the ovulation phase starts.

• OVULATION

This phase consists of

all the days when it is possible that the ovary could release the egg

into the

oviduct.

When

the egg is released during this period varies from person to person.

But the egg is released sometime during this period when the ovary gets a high shot of

Lieutinising Hormone

from the

pituitary gland.

The follicle in the ovary bursts open and the egg is released into the oviduct.

After ovulation, the luteal phase begins, which ends at the start of menstruation.

• LUTEAL PHASE

During this phase, the body

thickens the lining of the uterus

to prepare for implantation of a zygote in case

fertilisation

happens.

This is done via some hormones, most prominently

progesterone

which is secreted in large amounts by the

burst ovarian follicle

that released the egg, which is now called the

corpus luteum

.

The follicle continues to secrete progesterone until menstruation and then dies off.

AND then all of it starts all over again.

The whole menstrual cycle takes 28 days.

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Well that was very much it.

Following are some significant details which tie in to the various stages.

Here is an overview with all the important hormones:

Notice how

Lieutinising Hormone

levels rise during ovulation and how much the burst follicle (

corpus luteum

) secretes

progesterone

after ovulation.

Here you can see the

thickness change of the uterus lining

throughout the cycle:

Notice how much of the thickness is

related to the amount of progesterone

secreted (spoiler: a lot!)