Antenatal Care and Screening

Question 1

What percentage of pregnant women are affected by morning sickness?

Answer 1

80-85%

Question 2

When is morning sickness worst?

Answer 2

Usually worst in first 16 weeks with most women feeling much better after this
Exacerbated by any condition with excess human chorionic gonadotrophin such as a molar pregnancy or multiple pregnancy

Question 3

What condition can morning sickness progress to?

Answer 3

Hyperemesis gravidarum

Question 4

How does cardiac output vary in pregnancy?

Answer 4

Increases by 30-50%

Question 5

How is cardiac output increased in pregnancy?

Answer 5

Through combination of an increased stroke volume and heart rate (can cause palpitations)

Question 6

When does blood pressure drop during pregnancy and what factors cause this?

Answer 6

During the second trimester due to the following:

• Expansion of the uteroplacental circulation
• A fall in systemic vascular resistance
• A reduction in blood viscosity
• A reduction in sensitivity to angiotensin

Question 7

When does blood pressure return to normal following the decrease in the second trimester?

Answer 7

During the third trimester

Question 8

What changes occur in the urinary system during pregnancy?

Answer 8

Increased urine output
Renal plasma flow increased by 30-50%
GFR increased by 50%
Decrease in serum urea and creatinine (partly due to increased GFR, more so due to dilutional effect of increased plasma)
Bladder capacity decreased in third trimester due to enlarged uterus
More difficult to empty bladder so UTIs more common
Hydronephrosis physiological in third trimester so pyelonephritis more common

Question 9

What complication can be associated with UTIs in pregnancy?

Answer 9

Preterm labour

Question 10

What haematological changes occur during pregnancy?

Answer 10

Plasma volume increases by ~50%
Red blood cell count increases by 25%
Dilution causes decreased haemoglobin concentration
Iron requirements higher during pregnancy
White cell count increased
Platelet count decreased by dilution

Question 11

When should iron supplements be given during pregnancy?

Answer 11

If haemoglobin is <110 at booking or <100 on routine testing at 28 weeks

Question 12

What respiratory changes occur during pregnancy?

Answer 12

Progesterone acts centrally to reduce CO2
Tidal volume, respiratory rate and plasma pH increased
O2 consumption increases by 20%
Plasma PO2 unchanged
Hyperaemia of respiratory mucous membranes occurs

Question 13

What gastriointestinal changes occur during pregnancy?

Answer 13

Oesophageal peristalsis is reduced
Cardiac sphincter of stomach relaxes
Gastric emptying slows
GI motility reduced due to increased progesterone and decreased motilin in pregnancy

Question 14

What portion of pregnancies in Scotland are unplanned?

Answer 14

1/3

Question 15

What are the commonest causes of maternal death in pregnancy?

Answer 15

Cardiac disease
Thromboembolism
Other indirect
Psychiatric
Sepsis

Question 16

What can pre-pregnancy counselling involve?

Answer 16

General health measures (improve BMI, reduce alcohol consumption)
Smoking cessation
Folic acid consumption
Counselling of mothers with pre-existing health problems to ensure the following:
- Optimise maternal health
- Maintain psychiatric health
- Stop or change and unsuitable drugs
- Advise regarding complications associated with maternal medical problems
- Occasionally advise against pregnancy (especially in cardiac and renal disease)

Question 17

What counselling can be given regarding problems in pregnancy?

Answer 17

Counselling regarding possible recurrence of caesarean section, DVT, pre-eclampsia, pre-term delivery, intrauterine growth restriction and fetal abnormality. Actions to reduce these risks can include thromboprophylaxis, low dose aspirin, treatment of infection and folic acid.

Question 18

What infections are screened for antenatally?

Answer 18

Rubella
Hepatitis B
Syphilis
HIV
UTI

Question 19

When are anomalies screened for on ultrasound?

Answer 19

At 12 and 20 weeks

Question 20

What anomalies can be detected on a 12 week ultrasound?

Answer 20

Ensure pregnancy viable
Multiple pregnancy
Identify abnormalities incompatible with life
Offer and carry out Down’s syndrome screening

Question 21

What can be checked on a 20 week ultrasound?

Answer 21

Systematic structural review of baby
Not possible to identify all problems
Can identify problems that need intrauterine or postnatal treatment

Question 22

What is the overall risk of Down’s syndrome?

Answer 22

1:700

Rises to 1:150 in high risk individuals

Question 23

What factors increase risk of Down’s syndrome?

Answer 23

Increasing maternal age

Family history of chromosomal abnormality

Question 24

What chromosomal abnormality causes Down’s syndrome?

Answer 24

Trisomy 21

Question 25

When is Down’s syndrome screening carried out?

Answer 25

10-14 weeks

Question 26

How is Down’s syndrome screened for?

Answer 26

Using:

• Maternal risk factors
• Serum Beta-hCG
• Pregnancy associated plasma protein A
• Fetal nuchal translucency measurement

Question 27

When is further testing for Down’s syndrome offered?

Answer 27

When screening indicates a risk of >1:150

Question 28

How is further testing for Down’s syndrome done?

Answer 28

Non-invasive prenatal testing (not available on NHS)
Amniocentesis
Chorionic villus sampling

Question 29

When can amniocentesis and chorionic villus sampling be done?

Answer 29

Amniocentesis- 15 weeks on

Chorionic villus sampling- 10-14 weeks

Question 30

What risks are associated with amniocentesis and chorionic villus sampling?

Answer 30

Both associated with ~1% risk of miscarriage