Intraventricular hemorrhage (IVH) is bleeding into cavities in the brain called the ventricles. The blood vessels in the immature brain, including those in the germinal matrix next to the ventricles, are weak. The germinal matrix is a part of the brain that is active during fetal development but that disappears at about the 35th week of pregnancy. The blood vessels are thin, fragile, and vulnerable to fluctuations in blood flow, which can cause them to rupture and bleed.
The younger and smaller the baby, the higher the risk these blood vessels may be ruptured, usually in the first few days of life. A rupture causes blood to flow into one or both ventricles. The ventricles of the brain are normally filled with cerebrospinal fluid (CSF).
Severe IVH may first be suspected just by looking at the baby. Because the ventricles in the brain are filling up, pressure is created. Since the skull bones have not fused, a swelling of the head or the soft bones at the top of the head called the fontanelles, may be visible. Also, because weakened blood vessels in the brain are susceptible to damage from sudden blood pressure changes, abnormal blood pressure readings may alert medical staff to the possibility of IVH.
Because IVH can occur due to injury, if the condition is suspected, the circumstance of the premature baby’s birth, for example a particularly rough and prolonged labour, will be looked into, as will signs of infection, as they may be an indication of IVH.
Although IVH can have no initial symptoms, seizures, major clinical deterioration with anemia, hypotension, and metabolic acidosis may all be signs. At times, premature babies with IVH may appear not to be thriving and sickly in general.
A head ultrasound will be performed to confirm the diagnosis. Additional tests include blood work to check for anemia, metabolic acidosis, and infection. If IVH is confirmed, it will be classified on a scale from Grade I to Grade IV, which is the most severe.
Grades of IVH
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Grade I |
Subependymal or germinal matrix hemorrhage (SEH/GMH) |
The bleeding is restricted to the germinal matrix and blood has not entered the ventricles. |
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Grade II |
Intraventricular hemorrhage (IVH) |
Some blood is present in the ventricles, but not enough to enlarge them. |
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Grade III |
Ventriculomegaly (VM) |
Enough blood has entered the ventricles that the ventricles are enlarged. |
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Grade IV |
Parenchymal hemorrhage (IPH) |
The bleeding into the ventricles has resulted in a decreased blood supply to other parts of the brain, causing ischemic damage with subsequent bleeding. |