Three days after birth, a breastfeeding newborn becomes jaundiced. The parents bring the infant to the clinic, and blood is drawn for an indirect serum bilirubin level. The test result is 12 mg/dL. The nurse explains that it is physiologic jaundice, a benign condition, which is caused by:
1
immature liver function.
2
an inability to synthesize bile.
3
an increased maternal hemoglobin level.
4
high hemoglobin with low hematocrit levels.