Applied Embryology

Question 1

What are the most common anomalies?

Answer 1

Congenital heart defects

Question 2

How many babies are affected by neural tube defects?

Answer 2

1 in 1,000

Question 3

What is the prognosis for those with congenital heart defects?

Answer 3

6% die before their first birthday

Question 4

What percentage of babies are born with birth defects?

Answer 4

2.2%

Question 5

What is a teratogen?

Answer 5

An environmental exposure (such as a drug, substance or infection) to which the mother is exposed to during pregnancy which can result in birth defects in the foetus

Question 6

What can teratogens lead to?

Answer 6

• May detrimentally affect the developing embryo/foetus in utero
• May lead to structural or functional abnormalities or even IUD

Question 7

What effects can teratogens have on the developing foetus?

Answer 7

• Death
• Learning difficulties
• Sensory deficient
• Structural abnormalities
• Cancer
• IUGR or growth defects
• Neurodevelopmental / behavioural dysfunction
• Developmental delay

Question 8

When can adverse effects occur in utero?

Answer 8

At any stage in the pregnancy

Question 9

When do structural defects take place?

Answer 9

In the first trimester during organogenesis

Question 10

When is the greatest risk of structural defects?

Answer 10

Between weeks 3 and 11

Question 11

When are functional and growth defects most likely to occur?

Answer 11

After 12 weeks of gestation

Question 12

Give examples of drug teratogens.

Answer 12

• Carbamazepine
• Phenytoin
• Tetracyclines
• Sodium valproate
• Diethylstilboesterol
• Thalidomide
• Alcohol
• Cigarette smoke
• Illegal drugs
• Retinoids

Question 13

What is binge drinking?

Answer 13

When an individual drinks 5 or more units of alcohol on one occasion

Question 14

When is binge drinking particularly harmful?

Answer 14

Around conception and in early pregnancy

Question 15

What is heavy drinking often related to?

Answer 15

Unprotected sex which may lead to unplanned pregnancies and STIs

Question 16

What is the classic triad for congenital rubella syndrome?

Answer 16

• Sensorineural deafness
• Eye abnormalities (especially retinopathy, cataract and microphthalmia)
• Congenital heart disease (especially pulmonary artery stenosis and patent ductus arteriosus)

Question 17

What can varicella in a foetus lead to?

Answer 17

• Limb hypoplasia
• Skin scarring
• Eye defects

Question 18

When does varicella pose the greatest risk to foetuses?

Answer 18

During the 2nd trimester

Question 19

When does cardiac development take place?

Answer 19

Between weeks 3 and 6

Question 20

Give examples of drugs that can interfere with cardiac development.

Answer 20

• Warfarin

- Lithium

Question 21

How is the link between teratogens and foetal abnormalities made?

Answer 21

• Clinicians noticing patterns such as rubella and thalidomide
• Epidemiology/ ecological studies

Question 22

What can opiate medications given for maternal pain during labour cause in the baby?

Answer 22

• Respiratory depression
• Effect on brain
• Effect on skeleton
• Growth restriction

Question 23

Who is preconception counselling vital for?

Answer 23

• Epileptics
• Diabetics
• Women on anticoagulants
• Women with congenital anomalies
• Women on anti-hypertensives

Question 24

When should women start taking folic acid?

Answer 24

Around 3 months before they aim to fall pregnant

Question 25

When does the neural tube close?

Answer 25

Around day 30

Question 26

What is the standard dose of folic acid for those who are pregnant?

Answer 26

400micrograms per day

Question 27

What dose of folic acid should those with an increased BMI, epilepsy or diabetes take?

Answer 27

5milligrams per day

Question 28

How much vitamin D should pregnant women take?

Answer 28

10 micrograms