The perpose of this study to prove the significance of the hypothesis that there will be a significant improvement in motor development when remote tele-rehabilitation treatment is performed for extremely premature infants. The investigators plan to recruit subjects who meet the inclusion criteria and do not meet the exclusion criteria from among extremely premature infants born at Samsung Hospital, Seoul, Korea, whose gestational age is from 23 weeks to 28 weeks. The target number of n is 110, 55 per group. After randomization into an intervention group and a control group, the intervention group get the intervention starting at 0 months of correctional age and runs for 3 months. In both groups, motor outcomes are measured at the time of enrollment, at 3 months of correction age, 6 months of correction age and 12 months of correction age
This study is to prove the effectiveness of home based early intervention of extremely premature infant by Parent.