Intrauterine Growth Curve of Twins on the Basis of Gestational Age

Kim, Suk Young; Kim, Gwang Joon; Kim, Yong Wook; Lee, Jee Sung; Hwang, Byung Chul; Choi, Yoo Duk

Abstract

OBJECTIVE
In order to investigate more accurate patterns of intrauterine growth in twin fetuses, we constructed the twin-specific growth curve based on gestational age in live-born non-anomalous infants. METHODS: 563 twin pairs, 1,126 infants delivered between January 1994 and October 1999 were comprised our study population. The newborns were grouped according to gestational age and the median, 10th, 50th, and 90th percentile birth weight for each gestational week were calculated. Curves were plotted for the general population and for each gender and parity and compared with previously reported singleton's growth curve. RESULTS: After 32 weeks gestation, birth weight of twins falls below that of singleton, so that by 38 weeks the 50th percentile for twins falls below the singleton 10th percentile. This difference was also present among all subgroups of twins, such as gender and parity. And the mean birth weight in male twin infant was heavier than in female twin infant throughout all gestational week. CONCLUSION: The pattern of growth in twin infants differed from those of singleton. We recommend twin-specific growth curve for clinical use in the management of twin gestations.