[Effect of obstetric factors on neonatal hypoxic-ischemic brain injuries]

To determine the effect of high risk obstetric factors on neonatal hypoxic-ischemic brain injuries. The obstetric factors were investigated, including maternal complications during pregnancy and labor, the mode of delivery.

Intensive B-ultrasound brain monitoring in 211 newborns within the first 48 hours of life was carried out. The abnormalities were followed up by B-ultrasound. We assessed the extent of hypoxic-ischemic brain injuries with two kind of types, mild and severe. The mild type included 1-2 degree intracranial hemorrhage and the local hypoxic-ischemic encephalopathy. The severe type included 3-4 degree intracranial hemorrhage and extensive cerebral edema.

Thirty-nine cases (18.5%) were diagnosed intracranial hemorrhage and 22 cases (10.4%) were diagnosed hypoxic-ischemic encephalopathy (HIE) or cerebral edema. The total positive rate was 28.9%. Of the positive cases, 67.2% were mild brain injuries without clinical symptoms. Those cases need no medical treatment and recovered in a natural course. The rates of brain injuries in groups of pregnancy induced hypertension, fetal distress, neonatal asphyxia and premature newborns, were 46.1%, 48.9%, 66.7% and 71.4% respectively. It suggested that high risk obstetric factors were closely related to neonatal brain injuries. 15.9% of positive cases were from normal mothers without any obstetric complications. The brain injuries in those cases were mild.

The study showed that as a non-invasive procedure, B ultrasound brain examination is necessary for newborns with perinatal high risk factors of brain injuries. The study also suggested that perinatal care and systematic fetal monitoring were key-points for reduction of neonatal brain injuries.