Congenital Defects and Human Embryology Flashcards
Outline how genetic factors can cause congenital defects
Trisomy, for example, Downs Syndrome
Outline how drugs may lead to congenital defects
Acne medication such as Accutane and thalidomide can interact with foetal development
Outline how environmental factors cause congenital defects
Infectious agents such as rubella or zika virus, or alcohol can cause defects
How is consumption of folic acid beneficial in pregnancy?
Can prevent up to 75% of neural tube defects if 400mg taken daily prior to and during 1st trimester
What is meant by the embryonic period of development?
Weeks 3 to 8
What is meant by the foetal period of development?
Weeks 8 to 38
When is there a higher risk of congenital defect occurring in development?
Embryonic period
What is likely to be the consequence of damage in the embryonic period of development?
Major morphological abnormalities
What is likely to be the consequence of damage in the foetal period of development?
Functional defects and minor morphological abnormalities
Explain what is meant by a major congenital defect
Affects ~6% of newborns and requires surgical/medical intervention as it causes significant handicap
Explain what is meant by a minor congenital defect
Affects ~15% of newborns and doesn’t require intervention as it only causes minimum handicap
Name some examples of major congenital defect
Anencephaly, cleft lip and cleft palate, omphalocele, gastroschisis, spinal bifida
Name some examples of minor congenital defects
Ear tag or pit, supernumerary nipples, cryptorchidism, polydactyly, micropenis
What is ‘situs inversus’
This is when the organs of the body are in a mirrored anatomy to what is expected e.g. Heart on the right, stomach on the right, liver on the left
Name the 3 most common causes of congenital defects
Genetic abnormalities, drug use of environmental factors
