Abstract:
Objective
To study the influencing factors of hyperbilirubinemia in preterm infants.
Methods
A total of 237 cases of preterm infants under 37 weeks of gestational age diagnosed with hyperbilirubinemia were selected, who received phototherapy in Shengjing Hospital of China Medical University from June 2013 to Dec. 2016, and they were included as the observation group. A total of 142 preterm infants without hyperbilirubinemia hospitalized during the same period were chosen as the control group. Compare the gestational factors of the mothers，  the general condition of the preterm infants and their relationship with the diseases in preterm infants between the two groups.
Results
The cesarean section rate of observation group was 43.5%（103/237）， the rate of 1 min Apgar score≤7 was 22.8%（54/237）， and the rate of time of first meconium＞24 h was 27.4%（65/237）， all being higher than those of control group（25.4%,11.3% and 17.6%，respectively）， and there was statistical difference（P<0.05）. The incidence rate of acidosis（18.6%，44/237），neonatal sepsis（EOS/LOS）（8.4%,20/237）, neonatal hemolysis disease(5.9%,14/237), and suppurative meningitis(2.53%,6/237) was significantly higher than that of control group(18.3%,0.7%,1.4% and 0.7%, respectively), the difference being statistical(P<0.05). The gestational age of the observation group［(33.8±2.1)weeks］ and the birth weight［(2 259±515)g］ were significantly lower than the control group（P<0.05）. The hemoglobin level［(170±21)g/L］ was higher in the observation group than in control group［(163±22)g/L］(P<0.05). Multi-factor Logistic regression analysis showed that the 1 min Apgar score≤7（OR=8.189，P<0.05）, cesarean section（OR=2.461，P<0.05）， the time of first meconium>24 h（OR=3.214，P<0.05）, neonatal sepsis（EOS/LOS）（OR=45.385，P<0.05）， and high level of hemoglobin（OR=1.024，P<0.05） were the risk factors of hyperbilirubinemia in preterm infants.
Conclusion
Many perinatal factors can lead to hyperbilirubinemia in the preterm infants. It will reduce the incidence of hyperbilirubinemia in preterm infants to improve delivery technique， detect early and give timely gastrointestinal feeding.

Key words: Hyperbilirubinemia, Influencing factors, Preterm infants