Estimated 1-2 infants per 1000 live births.
10-20% of affected infants do not survive.
Typically are full or near term infants with associated congenital abnormalities and respiratory failure requiring ventilation shortly after birth.
Characterized by postnatal persistence of increased pulmonary vasculature resistance causing a right-to-left shunting of blood through a patent ductus arteriosus, foramen ovale or both, diminished pulmonary blood flow and hypoxemia.
Occurs when the circulatory system of a newborn baby fails to adapt to life outside the womb; it is characterized by high resistance to blood flow through the lungs, right-to-left cardiac shunting and severe hypoxemia.
Pulmonary vascular resistance in fetal circulation fails to decrease at birth.
Results in right to left shunting of blood through fetal channels, diminished pulmonary blood flow and marked hypoxemia.
Occurs in term or near term infants and is associated with hours of birth with severe respiratory failure requiring mechanical ventilation.
Infants that survive have chronic lung disease, seizures, and neurodevelopment problems due to hypoxemia, and aggressive treatments.
Increased risk of PPHN with maternal use of SSRIs in late pregnancy, but the absolute risk is small.