[Intrauterine growth of live-born Japanese infants between 28 and 42 weeks of gestation].

: Intrauterine growth of live-born infants between 28 and 42 weeks of gestation has been measured by birth weight. All live-born infants in Miyagi prefecture where is situated at the middle part of Japan were 31,534 from February, 1978 to January, 1979. Out of the 31,534 live-born infants, there were 11,025 cases whose records were incomplete, because of uncertainty concerning duration of pregnancy. So, we investigated 19,509 live-born infants. Most of them were born at term (37 to 41 weeks of gestation). Premature delivery rate was 3.36% and postterm delivery rate was 3.78%. Finally, we made the intrauterine growth curves derived from 19,509 live-born infants at each week of gestation and weights for 10th, 50th and 90th percentile.