Prevalence and Risk Factors of Intraventricular Hemorrhage in Premature Newborns less than 35 Weeks in Neonatal Intensive Care Units of Isfahan

Background:
Intraventricular hemorrhage (IVH) is an important cause of mortality and morbidity in premature infants. IVH can cause motor deficit, cerebral palsy, behavioral and intellectual disability in preterm newborns. The aim of this study was to assess the prevalence and risk factors of IVH in premature infants with a gestational of less than 35 weeks.

Methods:
From 2003-2005 we prospectively studied 167 preterm newborns less than 35 weeks at Alzahra and Shahid beheshti hospitals- Isfahan- Iran. Skull sonography performed at 7th day of life and IVH graded from grade 1-4. The exclusion criterion was neonatal death before the 7th day of life. Brain sonography was conducted at day 7 after birth, and IVH was categorized to four degrees. The association of maternal and neonatal characteristics with IVH was evaluated.

Findings:
The prevalence of IVH was 19.5% in newborns < 35 weeks and 25% in newborns < 1500 grams. The prevalence of IVH significantly correlated with gestational age (p=0.005) and low birth weight (p= 0.002). From 167 infants, 9(5.3%) had grade 1 IVH, 14(8.3%) had grade 2 IVH, 9(5.3%) had grade 3 IVH and 1(0.5%) infant had grade 4 IVH. The other important risk factors for IVH were low 5-minute apgar score, duration of mechanical ventilation, vaginal delivery, duration of oxygen therapy, endotracheal suctioning, low platelet count and surfactant use.
The protecting factors included maternal steroids therapy, higher birth weight and higher gestational age.

Conclusion:
This study emphasizes on the importance of recognizing the risk factors of IVH. With reduction of these risk factors, the incidence of this critical disease can be reduced in newborns.

Key words:
Intraventricular hemorrhage, preterm infant, risk factors