Randomized Controlled Trial for the Prevention of Intraventricular Hemorrhage by Indomethacin in Japanese Extremely Low Birth Weight Infants.

INTERVENTION: A dose of intravenous injection of 0.1 mg /kg of indomethacin will be given continuously in 6 hours. Two additional dose will be given in the same manner in every 24 hours. Administration will be completed when the third administration is completed. Placebo (A same dose of intravenous indomethacin of 0.1 mg /kg) will be given continuously in 6 hours. Two additional dose will be given in the same manner in every 24 hours. Administration will be completed when the third administration is completed. CONDITION: Extremely Low Birth Weight Infants (Intraventricular Hemorrhage , Patent ductus arteriosus) PRIMARY OUTCOME: 1. Incidence of grade 3, 4 Intraventricular hemorrhage on day 6.; 2. Incidence of Patent ductus arteriosus on day 6.; 3. Incidence of Periventricular Leukomalacia, Necrotizing Enterocolitis, Retinopathy of prematurity SECONDARY OUTCOME: 1.Developmental impairment at 1 and a half year old.; 2.Developmental impairment at 3 years of age.; 3.Mortality rate at 0‐27 days after birth.; 4.Requirement of surgery for Patent ductus arteriosus. INCLUSION CRITERIA: 1.Extremely low birth weight infants weighing more than 400 g and less than 1000 g at birth. 2.Gestation above 22 weeks 0 day at birth. 3.Birth weight standard deviation ‐1.99 sd. All infants born less than 24 weeks 0 day is to be included. 4.First dose to be given within 6 hours of birth. 5.Informed consent to participate to the study is obtained from the guardians.