Neonatal jaundice is one of the common symptoms during the neonatal period; it could be a normal physiological phenomenon, or it might be an external manifestation of certain diseases. Typically, physiological jaundice appears two to three days after birth, reaches its peak within four to five days in full-term infants, and may appear sooner and be more severe in preterm infants due to their less mature liver function. The peak period lasts longer for preterm babies; generally, in full-term infants, jaundice usually starts declining about a week later, subsiding around ten days, generally not lasting more than two weeks.