Pregnancy and birth

2. PREGNANCY AND BIRTH

3. • Human reproduction comes from two
different cells. These are the female
ovum and a male sperm.
• These cells carry genetic information
from each parent. This is why all
children are unique.
• Women’s bodies are designed to
house, nourish and protect a foetus.
HOW DOES IT START?

4. 1. FERTILISATION
• For fertilisation to occur the egg
must be released into the
fallopian tubes and sperm must
be deposited there.
• Sperm use their tails to swim up
the vagina to the ovum. One
sperm only can fertilise the
ovum.

5. 1. FERTILISATION
• Now that the ovum is fertilised, the cells can begin to divide and multiply.
• A ball of cells is created called a zygote.

6. 2. EMBRYO DEVELOPMENT
• The zygote then travels to the uterus. Here the cells continue to divide and multiply
turning them into an embryo.
• This embryo secures itself to the lining of the uterus so that it can grow.
• In 8 weeks time, the embryo will be around the size of an adult’s thumb.

7. FETUS DEVELOPMENT
• After around 9 weeks, all of the babies organs would have formed and the embryo
develops into a foetus.
• This foetus floats in a sac filled with amniotic fluid. This fluid protects the foetus from
knock and bumps.

8. FETUS DEVELOPMENT
• The mothers placenta supplies the foetus with oxygen and nourishment.
• The placenta is also used to transfer waste matter and carbon dioxide from the fetus to
the mother.
• The baby is connected to the placenta by the umbilical chord.

9. BIRTH
• Overall, the pregnancy will last around 280
days.
• When it is time for the baby to be born it
will push against the cervix which will then
start to open and widen.
• A key indicator of the beginning of birth is
when the amniotic fluid is released.

10. BIRTH
• As well as this, the muscles of the uterus
begin to contract.
• The baby is pushed through the cervix and
down the birth canal.
• Usually a baby is born head first. The
umbilical chord also comes out with the
baby, and is cut and tied.
• Finally the placenta comes out.

11. RESOURCES
• The natural science primary 6 book, written by Beatrice Sadovy.
• Kidshealth.org