Through this study our aim was to evaluate whether significant change in serum calcium level occurs in term newborns who are undergoing phototherapy and to find out the association between effect of phototherapy on serum calcium level and birth weight, postnatal age and type of feeding.

Jaundice is the yellow discoloration of skin, sclerae, and other tissues caused by the deposition of bilirubin.

Approximately 60% of term and 80% of preterm babies develop jaundice in the first week of life, and about 10% of breastfed babies are still jaundiced at 1 month. Jaundice is a common cause of readmission to hospital after early discharge of newborn infants.

The most common form of hyperbilirubinaemia observed in neonates is due to unconjugated or unbound bilirubin. High levels of unconjugated bilirubin are managed by treatment of the underlying cause (e.g. dehydration and sepsis), provision of phototherapy, administration of immunoglobulin (in certain cases of haemolytic anaemia) and, in very severe cases, exchange transfusion. If left untreated, extreme elevation of unconjugated bilirubin can lead to permanent brain damage (kernicterus) and/or death.

However, exchange transfusion is associated with a significant morbidity, and even mortality while phototherapy has several disadvantages which include increasing the duration of hospitalization, costs and mother-child separation . It also has some reported side effects as rash, loose green stools, dehydration, ocular hazards, oxidative injury, hyperthermia and water loss and may be associated with some long-term side effects such as melanocytic nevi, skin cancer, allergic disease, patent ductus arterious and retinal damage .

Some studies are available concerning the prevalence of hypocalcemia in neonates after phototherapy, but the results varied based on where the studies were conducted. So, more studies were required to reach a definite conclusion. Through this study our aim was to evaluate whether significant change in serum calcium level occurs in term newborns who are undergoing phototherapy and to find out the association between effect of phototherapy on serum calcium level and birth weight, postnatal age and type of feeding.

Inclusion Criteria:

• Stable term neonates with jaundice who require management with phototherapy and are fed with full strength formula or breast fed.

Exclusion Criteria:

• Jaundiced neonates with hypocalcemia.
• Jaundiced neonates needing exchange transfusion.
• Jaundiced neonates suffering from hypothyroidism.
• Jaundiced infants of diabetic mother.
• Jaundiced infants with other illness as severe RDS, perinatal asphyxia,Sever sepsis or hemolytic disease of newborn.
• Jaundiced infants with congenital abnormalities.

Infants who will come at neonatal unit of Assiut University Children's Hospital meeting our inclusion criteria.