The normal value of neonatal jaundice at 20 days is a range, which is generally considered to be physiological jaundice without meeting the criteria for phototherapeutic intervention, and is within 21 mg/dL for healthy term infants, 18 mg/dL for healthy preterm infants, and 15 mg/dL for preterm infants with high-risk factors (hemolysis of the newborn, cephalohematoma, subcutaneous bruising, asphyxia, hypoxia, etc.).
Neonatal jaundice is categorized into physiological jaundice and pathological jaundice. Physiologic jaundice is a symptom of jaundice due to the destruction of a large number of red blood cells in newborns after birth, resulting in the overproduction of bilirubin, which is weakly metabolized by the liver. It usually appears in 2~3 days after birth, reaches the peak in 4~5, and subsides naturally in about 7~10 days.
Pathological jaundice has more causes, such as breast milk, hemolytic, pediatric hepatitis, biliary atresia and so on, leading to excessive bilirubin production. Jaundice usually appears in the first 24 hours of a newborn’s life, and the jaundice value increases rapidly, exceeding 5 mg/dL per day.
Currently, according to the standard curve of postnatal hourly age phototherapy for neonates of different gestational ages and different risk factors, 20-day healthy term infants within 21mg/dL, 20-day healthy preterm infants within 18mg/dL, and 20-day preterm infants with high-risk factors within 15mg/dL are considered to be physiologically jaundiced.