The fetal circulation changes to normal
circulation at birth with
a) Closure of patent ductus arteriosus
b) Closure of ductus venosus
c) Increased activity of right Ventricle
d) Opening of fossa Ovalis
Correct Answer - A
Answer- A. Closure of patent ductus arteriosus
The increase in the concentration of oxygen in the blood leads to a
decrease in prostaglandins, causing closure of the ductus arteriosus.
These closures prevent blood from bypassing pulmonary circulation,
and therefore allow the neonate’s blood to become oxygenated in
the newly operational lungs