Lec 28: Overview of Congenital Malformations

Question 1

What is a malformation?

Answer 1

Structural abnormalities resulting from abnormal formation of tissues (intrinsic)

Question 2

What is a deformation (and a disruption)?

Answer 2

Structural abnormalities resulting from extrinsic causes (amniotic bonds, loss of blood supply, anoxia, etc).
Disruption is a more severe deformation.

Question 3

What is a syndrome?

Answer 3

A complex of malformations having a defined genetic cause

Question 4

What is an association?

Answer 4

Malformations that occur together in a nonrandom manner without a known cause

Question 5

What is a sequence?

Answer 5

Group of malformations linked to a single initiating event

Question 6

What percentage of newborns have a recognizable congenital abnormality?

Answer 6

2-3%

Question 7

What is an environmental agent that causes embryonic malformation?

Answer 7

A teratogen

Question 8

What is a critical period?

Answer 8

Period of maximum susceptibility to factors causing abnormal development (heart forms before palate, so earlier peak susceptibility)

Question 9

What is the most common type of congenital defect, and how common is it?

Answer 9

Heart defects; 1/100