Birth Weight Percentile In Normal Singleton Neonatal Birthweight At High Altitude

Objective:To develop local birthweight percentiles by gestational age,and for male and female singleton infants born in Kunming,China,and to study effects of maternal age and parity on birthweight.Material and methods:Cross-sectional analysis was conducted using perinatal database at out unit.The study population consists of all live births in the First Affiliated Hospital of Kunming Medical College between 1 January 1999 and 31 December 2008.During the study period,18,796 infants were delivered,after exclusion for stillbirth,maternal complications,and data missing,remaining 15830 birth for final analysis.Computer the raw birth weight for gestational,then non-linear regression models were used to smooth curves for each gestational age.Results:1.The mean birthweight in this study group were 3204g.2. 10^th,25^th,50^th,75^th,90⁹th) percentile of birthweighi were desctibed and the curves were successfully smoothed.3.The incidence of LGA in the hospital were 10.29%and SGA is 10.16%.4.The mean birth weight of male infant was 104g higher than female infant.After 36 weeks the difference in the mean birth weight were statistically significant.5.Parity were not related with significantly with birth weigt.Conclusions:We present recent birthweight percentiles by gestational age based on local data in Kunming.These percentiles provide current local norms for clinicians and researchers,and can provide a baseline for monitoring perinatal outcomes.