Birthweight by gestational age reference centile charts for Greek neonates

ObjectiveThe development of population based, sex-specific, birthweight for gestational age (GA) first-time reference centile charts for liveborn singletons in Greece. DesignSecondary analysis of national birth registry data ParticipantsData of birthweight by GA of all 633201 singleton live births in Greece between 2011 and 2017 were collected from the Hellenic Statistical Authority (ELSTAT). Main outcome measuresAfter excluding implausible birthweights, we estimated gender specific birthweight centiles for every gestational week from 22nd to 40th+ using the Lambda-Mu-Sigma (LMS) method via the GAMLSS package in R. Small (10th centile) and large-for GA (90th centile) cut-offs in certain gestational weeks were compared to previously published charts. ResultsMore than 90% of the 621043 neonates were born at term (>37 weeks of GA). The mean birthweight for boys and girls at 40+ weeks of GA were 3473 grams and 3327 grams respectively. Most neonates were born at 38 weeks of GA with a mean birth-weight of 3097 (97655 girls) and 3237 (104722 boys) grams. The proposed national centiles identified more or less deviant percentages of small and large for GA neonates in comparison to other (inter)national centiles. ConclusionsThe new centile charts provide important information on the contemporary distribution of birthweight for gestational age in Greece. They may assist physicians to classify high-risk neonates at birth based on national population data. Accurate identification of those in need of special care will help to prevent possible adverse sequelae in the perinatal period and beyond.