Defect Types & Examples

Question 1

Malformation

Answer 1

Intrinsic disturbance in morphogenesis, heritable

Ex: Holoprosencephaly, Cyclopia

Question 2

Disruption

Answer 2

Extrinsic disturbance in morphogenesis, secondary destruction of previously normally developed organ, not heritable
Ex: Amniotic bands

Question 3

Deformation

Answer 3

Extrinsic disturbance in development, compression of fetus due to abnormal biomechanical forces leading to structural abnormalities
Ex: Prune belly

Question 4

Sequence

Answer 4

Multiple congenital anomalies due to secondary effects of single localized aberration of organogenesis
Ex: Oligohydramnios (Potter) sequence

Question 5

Malformation Syndrome

Answer 5

Several defects that cannot be explained on the basis of a single localizing initiating error in morphogenesis
Ex: Down, Rubella embryopathy