Standard intrauterine growth curve of Thai neonates delivered at Rajavithi hospital.

OBJECTIVE To determine the distribution of Thai neonatal birthweights classified in gestational age and sex to create standard intrauterine growth curves of Thai neonates. MATERIAL AND METHOD A retrospective study was performed in Thai singleton pregnant women with confirmed gestational age between 24 and 42 weeks (168-294 days), delivered at Rajavithi Hospital. Birthweights were graphed as 5th, 10h, 50th and 90th percentile, and classified in gestational age as male, female, and both sexes. RESULTS In all 7,506 neonates: 3,973 male and 3,533 female, were included during the 4-year study period. The standard intrauterine growth curves at 5th, 10th, 50th, and 90th percentile in male neonates were higher in value but similar in shape than those in female neonates. CONCLUSION Male birthweights were higher but similar in shape compared with those of female in all gestational ages (24-42 weeks).