Antenatal screening

Question 1

What history points are required in the booking appointment

Answer 1

• Obstetric history
• Medical and surgical history
• Medications and allergies
• Mental health
• Family history
• Social history
• History of domestic abuse or violence
• Safety
• History of FGM

Question 2

What investigations are performed in the booking appointment

Answer 2

History
Weight
Height
Blood pressure

Question 3

What are some important mental health questions asked in the booking appointment

Answer 3

• Any new feelings that make you anxious or disturbed?
• Suicide or self harm?
• Feelings of incompetency as a mother?
• Feeling estranged from the baby?

Question 4

What are the criteria for oral glucose tolerance testing in pregnancy

Answer 4

• BMI > 30
• Previous macrosomic baby >4.5kg
• Family history of diabetes (1st relative)
• History of PCOS
• Ethnic family origin from area of high diabetes prevalence

Question 5

What are the main screening tests offered during pregnancy

Answer 5

• Infection
• Anaemia
• Rhesus status
• Haemoglobinopathy
• Down’s, Edward’s and Patau’s syndrome
• Foetal anomalies

Question 6

What is involved in antenatal infection screening

Answer 6

• Urine - Mid-stream urine sent
• Blood - HIV, Syphilis, Hepatitis B

Question 7

When is anaemia screening performed in pregnancy

Answer 7

FBC at booking scan and 28 weeks

Question 8

What are the 2 conditions screened for in haemoglobinopathy screening

Answer 8

Sickle-cell disease
Thalassaemia

Question 9

What is involved in haemoglobinopathy screening

Answer 9

Family origin questionnaire
Blood tests

Question 10

When is rhesus antibody screening performed in pregnancy

Answer 10

Blood grouping at booking and 28 weeks

Question 11

What is done if the mother is found to be rhesus D-negative

Answer 11

• Offer anti-D to prevent maternal antibody formation
• Routine prophylaxis at 28 weeks
• Additional anti-D for potentially sensitising events

Question 12

Describe the levels of trisomy screening in pregnancy

Answer 12

1. Quadruple screening

If high risk on 1. then:

2. NIPT

If high risk on 2. then:

3. Invasive foetal genetic testing (CVS or amniocentesis)

Question 13

What is used in the quadruple trisomy screen?

Answer 13

Crown-Rump length
Nuchal translucency
HCG levels
PAPP-A levels

Question 14

What is nuchal translucency

Answer 14

The thickness of fluid behind a babies neck

Question 15

When is quadruple trisomy screening done in pregnancy

Answer 15

11 - 13+6 weeks

Question 16

What is a normal NT value (If CRL is 45-84mm)?

Answer 16

<3.5mm

Question 17

What are some reasons why NT may not be measured?

Answer 17

• User error (Very specific measurement)
• Baby too small
• Baby in an unsuitable position

Question 18

What are the risks of higher NT values

Answer 18

Question 19

When is 2nd trimester trisomy screening offered?

Answer 19

If booking was too late for 1st trimester screening

If NT was not obtained during 1st trimester

Question 20

What is screened for in 1st trimester trisomy screening

Answer 20

Trisomy 13 - Patau’s syndrome
Trisomy 18 - Edward’s syndrome
Trisomy 21 - Down’s syndrome

Question 21

What is screened for in 2nd semester trisomy screening

Answer 21

Trisomy 21 - Down’s syndrome

Question 22

What tests are done in 2nd trimester trisomy screening

Answer 22

HCG and AFP

Question 23

When is 2nd trimester trisomy screening performed

Answer 23

15-20 weeks

Question 24

What risk of trisomy is considered high risk

Answer 24

1/150 chance

Question 25

What is the risk scale on trisomy screening

Answer 25

1/5000 - 1/2

Question 26

What does NIPT stand for

Answer 26

Non-invasive prenatal testing

Question 27

What is involved in NIPT

Answer 27

Maternal blood sample to detect cell free foetal DNA from the placenta

Question 28

What are the 2 main forms of invasive foetal genetic testing

Answer 28

Chorionic villous sampling (CVS) Amniocentesis

Question 29

When is CVS performed

Answer 29

11-14 weeks

Question 30

When is amniocentesis performed?

Answer 30

>15 weeks

Question 31

What is the miscarriage rate of CVS

Answer 31

<2%

Question 32

What is the miscarriage rate of Amniocentesis

Answer 32

<1%

Question 33

Is local anaesthetic required in invasive foetal genetic testing

Answer 33

CVS - Local anaesthetic Amniocentesis - No anaesthetic

Question 34

When is the mid-trimester anomaly screening performed?

Answer 34

18 - 20+6 weeks

Question 35

What are the benefits of the foetal anomaly screening programme (FASP)

Answer 35

Reduces mortality and morbidity and may allow in-utero management

Question 36

What 11 conditions are screened for on the FASP scan

Answer 36

- Anencephaly - Open spina bifida - Cleft lip - Diaphragmatic hernia - Gastroschisis - Exomphalos - Serious cardiac abnormalities - Bilateral renal agenesis - Lethal skeletal dysplasia - Edward’s syndrome (T18) - Patau’s syndrome (T13)

Question 37

What is open spina bifida

Answer 37

A congenital condition in which there is failure of the neural tube to close, meaning the spinal cord comes outside of the foetal spine in a sac

Question 38

What is gastroschisis

Answer 38

A birth defect where there is a hole in the abdominal (belly) wall beside the belly button. This results in the baby's intestines extending outside of the baby's body. Sometimes other organs, such as the stomach and liver, can be found outside of the baby's body.