Background and Objectives: Jaundice is a common disorder in preterm and term newborns and G₆PD deficiency is one of its etiologic agents. With respect to high incidence of G₆PD deficiency in Iran, this study was conducted to determine the clinical correlation of this deficiency with time of jaundice onset and mean level of serum bilirubin. Management and complication rates are also evaluated in these neonates in comparison with those without this deficiency.

 Methods: This is a case-control study performed through G6PD assay in icteric newborns admitted to neonatal intensive care unit in 22 Bahman hospital in Mashhad within 3 years. This case group was compared with the control group who were randomly selected from among icteric neonates without G₆PD deficiency. The data were collected by a questionnaire and analyzed by SPSS.

  Results: This study was done on 505 icteric neonates. The case group consisted of 34 newborns (6.7%) with G₆PD deficiency. M/F ratio in case group was higher than control group (P= 0.01). Mean level of total serum bilirubin was significantly higher in case group (P=0.047). There were no significant differences in duration of phototherapy and hospitalization between two groups, but exchange transfusion rate in case group was twice as much. Complications such as seizure and kernicterus in both groups were the same.

 Conclusion: Due to high incidence of G₆PD deficiency in our study (6.7%) and significant incidence in female patients, determination of enzyme level is recommended in all newborns with jaundice regardless of their gender. Because of higher level of serum bilirubin in G₆PD deficient patients, phototherapy must be done as soon as possible to avoid invasive procedures such as exchange transfusion.