IGF1 and asphyxia: As therefore could be deduced from the presented studies, a transient increase in the IGF-1 level in neonatal brains during the first 24 h after hypoxic-ischemic insult leads to an inhibition of oligodendroglial proliferation, which is afterwards compensated for by the increased number of dividing cells in the later period after perinatal asphyxia, when IGF-1 stabilizes at the physiological level.