10. Fetal abnormalities

Question 1

Developmental defects detected at birth

Answer 1

2.4%

Question 2

Developmental defects detected in infancy and childhood

Answer 2

2.5%

Question 3

Causes of Developmental defects

Answer 3

Genes=25%

Teratogens= 10%

Unknown= 65%

Question 4

biological teratogenic agent

Answer 4

Rubella (German Measles)

Question 5

Physical teratogenic agent

Answer 5

x-rays

Question 6

Chemical teratogenic agent

Answer 6

thalidomide

Question 7

Pre-implantation Diagnosis

Answer 7

IVF

FISH

PCR

Question 8

Post Implantation Diagnosis

Answer 8

Maternal Blood Biochemistry (MBB)

Chorionic Villus Sampling (CVS)

Amniocentesis

Cordocentesis

Fetoscopy

Scanning Ultrasound

Non-Invasive Prenatal Testing/Diagnosis

Question 9

Amniocentesis risk of miscarriage

Answer 9

0.25-0.5%

Question 10

Chorionic Villus Sampling risk of miscarriage

Answer 10

0.5-1%

Question 11

Cordocentesis risk of miscarriage

Answer 11

1-2%;

Question 12

Fetoscopy risk of miscarriage

Answer 12

12%

Question 13

Nature of NTDs

Answer 13

open or closed

May cause paralysis below level of the defect

bowel and/or bladder function

hydrocephalus/Death

Question 14

Spina bifida

Answer 14

NTD at spinal levels

Question 15

Anencephaly

Answer 15

NTD at brain level

Question 16

Answer 16

Spina bifida occulta

Question 17

Answer 17

Meningocoele

Question 18

Answer 18

myelomeningocoele

Question 19

Answer 19

Anencephaly

Question 20

Preventing NTDs

Answer 20

• Folic acid
• Found in broccoli, brussel sprouts, strawberries etc
• supplements at 400 micrograms /day from before conception
• prevents 70% of NTDs
• But 30% are resistant

Question 21

Factors Predisposing to NTD

Answer 21

• Hyperthermia (possibly)
• Hypervitaminosis A
• Diabetes
• Anti-epileptic drugs -Sodium Valproate and carbamazepine