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Flashcards in Ante and postnatal screening Deck (44)
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1

What does antenatal and postnatal screening involve?

Testing for diseases or conditions in a fetus or embryo before it is born

2

What does antenatal screening identify?

The risk of a disorder so that further tests and a prenatal diagnosis can be offered

3

What do common antenatal testing procedures include?

ultrasound scanning, amniocentesis, chorionic villus sampling (CVS) and rhesus antibody testing

4

What are three uses of an ultrasound used to produce?

An ultrasound image on a computer screen ,gestational dating scan and anomaly scan

5

What is a gestational dating scan mean?

which is used to determine the stage of pregnancy and date that the baby is due

6

What is an anomaly scan?

Used to detect the presence of serious physical problems in the fetus

7

What is an ultrasound?

image on a computer screen

8

Why are biochemical tests carried out?

To detect marker chemicals that are produced during normal physiological changes that take place during pregnancy

9

What is a screening procedure?

Tests such as ultrasound imaging that indicates the possible presence of a disorder

10

What can diagnostic tests like amniocentesis and CVS confirm?

The presence of conditions such as down syndrome

11

What can cells from amniocentesis and CVS do?

Be cultured to obtain sufficient cells to produce karyotype

12

What is karyotype?

An image of an individual's chromosomes arranged in homologous pairs

13

Why is a karyotype used?

To identify anomalies in the number or structure of chromosomes

14

What are problems with diagnostic test like amniocentesis and CVS?

THey are invasive and carry a small risk of inducing miscarriage

15

When can CVS be carried out?

Before amniocentesis but has a higher risk of inducing miscarriage

16

Why is Rhesus antibody carried out earlier in a pregnancy?

To determine the rhesus status of the mother, to ensure that she shows no immune responses to her fetus

17

what complications can event of a second pregnancy

If a mother is rhesus negative and the fetus is rhesus positive

18

What is given to negative rhesus mothers after sensitising events such as the birth of a baby?

Anti rhesus antibodies

19

What does postnatal screening involve?

Health checks that are carried out after the birth of the baby. These are aimed at detecting certain conditions or abnormalities

20

What is postnatal testing used to detect?

Metabolic disorders such as phenylketonuria (PKU)

21

What is PKU?

An inborn error of metabolism

22

How is PKU caused?

By an autosomal recessive genetic disorder

23

What can individuals with PKU cannot do?

Metabolise excess phenylalanine

24

What can happen if PKU is not detected soon after birth?

The baby's mental development can be affected

25

What do people with PKU have to do?

Be placed on a restricted diet that lacks the amino acid phenylalanine

26

What are pedigree charts compiled and used to analyse?

Patterns of inheritance in genetic screening and counselling

27

What are pedigree charts constructed to do?

Provide information and advice in situations where there is the possibility of passing on a genetic disorder to potential offspring

28

What are pedigree charts compiled to do?

To analyse patterns of inheritance in genetic screening and counselling

29

In what situation are pedigree charts used to provide information and advice?

Where there is a possibility of passing on a genetic disorder to potential offspring

30

What can pedigree charts be used to analyse?

Patterns of inheritance involving autosomal recessive, autosomal dominant, incomplete dominance and sex linked recessive single gene disorders