Background: Growth assessment including birth weight, length, and head circumference is important to identify infants at risk. However, using international growth curves may be inappropriate for growth assessment of Thai neonates.

Objective: To generate a growth chart of infants at the Phramongkutklao Hospital (PMK), and to compare PMK’s growth chart assessment with other international growth charts.

Materials and Methods: The authors generated a PMK growth chart from PMK’s newborn database between 2007 and 2016. Birth weight of infants born in 2017 was assessed by using the PMK growth chart in comparison with the Fenton, Lubchenco and Intergrowth Twenty-first growth charts.

Results: To generate a PMK growth chart, 22,926 infants were enrolled to the present study. Comparing with other international growth charts, the Fenton exhibited a higher ninetieth percentile of birth weight than others, especially at gestational age of 36 to 41 weeks. In contrast, the Lubchenco exhibited the lowest tenth percentile of birth weight. In 2017, 2,314 infants were born and evaluated by using the PMK, the Fenton, the Lubchenco, and the Intergrowth-21st growth charts. Large for gestational age (LGA) was identified in 185 (8.64%), 55 (2.57%), 166 (7.75%) and 166 (7.75%) infants, respectively. In contrast, small for gestational age (SGA) was identified in 220 (10.27%), 228 (10.64%), 34 (1.59%) and 148 (6.91%) infants, respectively. The admission rate of infants diagnosed as LGA by PMK, but appropriate for gestational age (AGA) by Fenton was higher than other AGA infants.

Conclusion: The PMK reference of neonatal growth is up-to-date and applicable. Growth assessment using the Fenton growth chart at late preterm and term gestations may be inaccurate to identify LGA infants. In contrast, the Lubchenco growth chart has limitation to identify SGA infants. Data accumulation from multi-centers at different regions of Thailand are warranted to generate a Thai neonatal growth reference.

Keywords: Growth curve, Neonatal growth, Large for gestational age, Small for gestational age

DOI: doi.org/10.35755/jmedassocthai.2020.12.10656

Received 25 September 2019 | Revised 13 July 2020 | Accepted 17 July 2020