4.6 pregnancy & 4.7 Childbirth

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• Leerjaar 2

4.6 pregnancy & 4.7 Childbirth

sperm vs egg

Sperm cells can survive for up to 4 days.

For fertilisation to occur, an egg cell must also be present in the fallopian tube.

An egg cell lives for approximately 12 to 24 hours after ovulation.

Getting pregnant

The egg cell must be fertilized by the sperm cell

Nucleus of the sperm cell must fuse with the nucleus of the egg cell

The fertilization

A nucleus of a sperm cell fuses with the nucleus of an egg cell,

this takes place in the fallopian tube.

Implantation: after about 6 days the ball of cells attaches itself to the thick uterine lining. Then the woman is pregnant

Pregnancy

0-8 weeks: Embryo

8 weeks to birth: Fetus

The placenta provides oxygen and nutrients and removes waste such as carbon dioxide so that it can be excreted by the mother.

Placenta

The placenta grows at the place where the embryo is implanted. The placenta contains capillaries (very thin blood vessels where gas exchange can take place).

Amniotic fluid and amniotic membranes protect the unborn child.

Amniotic membranes

Amniotic fluid

Prenatal testing

• 8-12 weeks: Ultrasound: Determine how long the woman has been pregnant
  
• From 10 weeks: NIPT test (non-invasive prenatal test) --> blood test (child's DNA) for DNA abnormalities.
  
• 13 weeks --> ultrasound for examination of abnormalities in the heart, brain, organs and limbs
  
• 20 weeks --> ultrasound (check) and gender can be determined

These transport egg cells.

1. vagina
2. sperm ducts
3. ovaries
4. fallopian tubes

In this, a fertilised egg can develop into a baby.

1. vagina
2. sperm ducts
3. ovaries
4. fallopian tubes

This is where the development of egg cells takes place.

1. vagina
2. uterus
3. ovaries
4. fallopian tubes

How often does ovulation occur in a fertile woman?

1. every 12 to 24 hours
2. approximately once every two weeks
3. approximately once every four weeks

An egg cell that is not fertilised dies.
What happens to the remains of the egg cell?

1. The remains leave the body along with the lining and blood during menstruation.
2. The remains are absorbed into the blood in the uterus.
3. The remains are absorbed into the blood in the fallopian tube.

4 stages of labour

Contractions --> muscles in the uterus contracts

Dilation --> cervix opening becomes wider

Expulsion --> baby is born

Afterbirth --> Placenta is pushed out

 

Make questions from 4.6 & 4.7 in your workbook