Up to half of full-time newborns become yellow during the first few days of life, more than premature ones.
Physiological jaundice is maximal at the age of 3-5 days. Milk jaundice occurs in about 10% of newborns up to 4-6 weeks of age. Jaundice is caused by excessive accumulation of bilirubin in tissues. This is due to the increased formation of bilirubin as a result of the breakdown of hemoglobin in the first days of life. The newborn’s liver is immature and its ability to degrade bilirubin is reduced. Neonatal intestinal meconium meeting the high content of bilirubin, which is absorbed by the body.
Prematurity is the most important yellowing factor. Blood group immunizations (ABO or Rh immunization) are the most common causes of severe yellowing. Other reasons include: infections, large bruises and nausea. In this case, the baby will often turn yellow before 2 days of age.
The yellow baby is sluggish and easily gets tired. Low milk intake and significant weight loss increase the risk of yellowing. Other risk factors for yellowing are maternal obesity and neonatal growth disorders.
Bilirubin levels can be monitored with a skin meter or blood sample. A skin meter is used as a screening tool in the ward. If necessary, a blood sample is taken.
When bilirubin levels rise sufficiently, yellowing is treated with blue light and adequate hydration. The light treatment limit depends on the gestational age of the child. Depending on the bilirubin level, 1-3 blue light bulbs or mattresses are used. Duration of treatment is based on bilirubin levels. In severe immunization, antibody therapy may be used and, in rare cases, blood exchange may be required.