Outcomes of infants born at periviable gestations in Japan

Abstract

In describing outcomes of neonates born at 22-23 weeks' gestation, Dr. Malamitsi-Puchner wrote that 'Even Japan, which has pioneered the active management of infants born at 22 weeks, has not reported improvements in death rates or cognitive and neurodevelopmental outcomes in the last 10 years'. 1 This is inaccurate, and we wish to correct the record.Multiple studies demonstrate that mortality in infants born at the earliest gestational ages has decreased in Japan. [2][3][4] In infants born at 22 weeks, Kono et al 3 reported that mortality decreased from 62.8% in 2003-2007 to 44.3% in 2008-2012, although no statistically significant changes were noted for death or neurodevelopmental impairment and death or cognitive delay (developmental quotient <70 on the Kyoto Scale of Psychological Development) at 3 years of age. Mortality rates by gestational age for all liveborn extremely preterm infants born at hospitals participating in the Japanese Neonatal Research Network are shown in the Figure 1.Although mortality has decreased for infants born at 22 and 23 weeks in Japan, and there has been a significant decrease in visual impairments and cerebral palsy reported at these gestations, the proportion of survivors affected by cognitive delay at 3 years has not improved. 2 A more accurate statement would be the following: 'Even in Japan, which has pioneered the active management of infants born at 22 weeks, improvements in mortality and morbidity are reported in infants born between 2003 and 2012, but not significant improvement in cognitive delay among survivors'. Fu n ding info r m at io n