A simple and easy to understand GCSE guide for student who're taking Biology. Written by Students for Students

1. Hormones and Menstrual Cycle
By Kashmala

2. The Menstrual Cycle
The menstrual cycle is a recurring process which takes around 28
days. During the process, the lining of the uterus is prepared for
pregnancy. If pregnancy does not happen, the lining is then shed.
This is known as menstruation.
Several hormones control this cycle – for example, they are involved
in controlling the release of an egg each month from an ovary, and
changing the thickness of the uterus lining.

5. Summary
During the Menstrual Cycle, a mature egg is
released from the ovaries about every 28 days.
The cycle is controlled by several; hormones
including FSH and Oesterogen

6. Examiner’s Tip & Keypoints
• Be clear on the difference between FSH and Oesterogen
• Make sure you know the difference between eggs maturing and
eggs being released.
• Hormones control the release of an egg from the ovary and the
build-up of the lining of the womb in the menstrual cycle
• Some of the hormones involved are FSH from the pituitary gland
and Oesterogen from the ovary

7. Control of Fertility
One of the most important and widely used ways of controlling fertility
is to use Oral Contraceptives.
The pill contains female hormones particularly oesterogen which
affect the woman's ovaries by preventing the release of any eggs.
The pill inhibits the production of FSH so no eggs can be matured
meaning the woman can’t get pregnant.
You have to use the pill regularly because if they forget to take it, the
artificial hormone level drops meaning their bodies hormones take
over rapidly. This can lead to an unexpected release of an egg -
enexpected baby

8. Contraceptive Pill
The first birth control pills contained very large amounts of
Oesterogen and caused many side effects such as high blood
pressure and headaches. Modern contraceptive pills contain much
lower doses of oesterogen and with some progesterone which
causes fewer side effects. Some contraceptive pills only contain
progesterone which cause even fewer side effects but don’t work
as good.

9. IVF Treatment
1. Fertility drugs are used to make lots of eggs mature at the same
time for collection
2. The eggs are collected and placed in a special solution in a petri
dish
3. A sample of Semen is collected and the fusion id done in the petri
dish
4. The eggs are checked to make sure they have been fertilised and
the early embryos are developing properly
5. When the fertilised eggs have formed tiny balls of cells, 1 or 2 of
the embryos are placed in the uterus of the mother. The baby
grows naturally from then on.

10. Keypoints
• Hormones can be used to control fertility
• Oral contraceptives contain hormones which help stop FSH so
more eggs are matured
• FSH can be used as a fertility drug for women to stimulate eggs to
mature in their ovaries. These eggs may be used in IVF
treatments.