Onset of Intraventricular Hemorrhage in Preterm Neonates Occurring Later in Life

Although the very early presenting form of intraventricular hemorrhage (IVH) in preterm neonates has declined, its overall prevalence has not changed significantly in the last 2 to 4 decades. These are the findings of a systematic review and meta-analysis published in JAMA Pediatrics.

Researchers explored the occurrence and temporal distribution of IVH in preterm neonates during the first week of life and whether recent improvements in neonatal care were associated with changes in occurrence and prevalence of IVH.

The researchers screened PubMed, EMBASE, Cochrane Library, and Web of Science databases for eligible studies and review articles and extracted data for the current analysis.

The researchers identified a total of 19,452 records from databases and 2115 from citation searches, of which 64 studies were included in the quantitative analysis and 2 were included only in the calculation of the severe IVH occurrence among preterm neonates. Overall, 9633 infants were included in the current analysis, with 51 studies reporting severe IVH events.

Based on data from the included studies, the overall occurrence of IVH was 33% (95% CI, 29%-37%) and severe IVH was 10% (95% CI, 8%-13%). These data were not different between subgroups before vs after 2007 (36% vs 31%; P =.19 vs 10% vs 11%; P =.67, respectively).

In studies before vs after 2007, the difference in IVH occurrence between subgroups of gestational age less than 28 weeks (33% vs 41%) and less than 32 weeks (32% vs 27%) was significant. Before vs after 2007, occurrence of severe IVH in infants with gestational age less than 28 and 32 weeks was 18% vs 17% and 7% vs 8%, respectively, supporting that more severe IVH is associated with lower gestational age.

Among preterm neonates, very early presenting IVH (up to 6 hours of life) was found to be significantly lower after vs before 2007 (5% vs 13%); for up to 24 hours of life, proportion of IVH was 18% vs 22%; and for up to 48 hours of life, it was 28% vs 18%, respectively.  

The proportion of very early presenting IVH decreased significantly after vs before 2007 (6 hours of life: 9% vs 35%; 24 hours of life: 25% vs 44%; 48 hours of life: 50% vs 82%, respectively).

One of the limitations of the analysis was the lack of accounting for the role of specific factors affecting the prevalence of IVH, such as gestational age, antenatal steroids, and birth settings.

“These data suggest that recently implemented preventive measures have the potential to postpone rather than reduce IVH in very preterm infants,” the researchers concluded.