Prenatal diagnostics

• Biologie
• Middelbare school
• vwo
• Leerjaar 4

Reproduction

Prenatal diagnostics

Learning objectives

• Describe different prenatal diagnostics techniques
• Describe pros and cons of different techniques
• Read a karyogram and draw conclusions

Prenatal diagnostics

Medical research before birth

Two categories:

- Invasive

- Non-invasive

Ultrasound

Chorionic villus sampling

NIPT

Amniocentesis

Invasive

Non-invasive

Ultrasound

Amniocentesis

Chorionic villus sampling

NIPT

Ultrasound

• Monitoring growth, bodily functions where possible, physical abnormalities
• 20 week ultrasound: health check

NIPT

• DNA from placenta taken from mother's blood
• Placenta DNA nearly identical to foetus DNA
• 11 weeks 

Chorionic villus sampling

• Sample beginning placenta
• Check for chromosome abnormalities
• 11-14 weeks
• 0,5% chance miscarriage 

Amniocentesis

• Collect amniotic fluid with genetic material foetus in there
• Check for genetic abnormalities
• 15-16 weeks
• 1/300 chance miscarriage

Which type of prenatal diagnostics provides no risk to the foetus?

1. Ultrasound
2. Chorionic villus sampling
3. Amniocentesis

Ultrasound cannot provide information on the following:

1. Confirm the length of the pregnancy
2. Identify specific chromosomal abnormalities
3. Indicate whether the foetus is alive
4. Locate the placenta

Karyogram

Chromosome portrait

Identify:

- Missing chromosomes

- Extra chromosomes

- Gender

Male

Female

Trisomy 21

Trisomy 13

Trisomy 18

Missing chromosome 11

Missing chromosome 19

Male

Female

Trisomy 21

Trisomy 13

Trisomy 18

Missing chromosome 11

Missing chromosome 19

Male

Female

Trisomy 21

Trisomy 13

Trisomy 18

Missing chromosome 11

Missing chromosome 19

Homework

Complete worksheet prenatal diagnostics on Classroom