Background: In Thailand, studies of growth date back to 1975, but there have been no studies examining any trends in increasing/decreasing growth.
Aim: To determine if there have been any secular trends of increasing/decreasing growth and/or ages at puberty in Thai children.
Methods: In 2012, a cross-sectional study of growth was conducted in 3460 children. The median heights and weights and the ages of pubertal maturation were compared with previous studies. Correlations between the secular trends and the health statistics indicators were calculated.
Results: From 1975-2012, the median final height of boys and girls had increased by 1.32 and 0.86 cm/decade and weight by 2.49 and 1.76 kg/decade, respectively. In girls, the age at thelarche and menarche had declined by 0.39 and 0.12 years/decade, respectively. In boys, the age at testicular enlargement Tanner II had declined by 0.15 years/decade. Increased physical growth was positively correlated to life expectancy, per capita income and prevalence of overweight/obesity was negatively correlated to prevalence of malnutrition and under-five mortality rate.
Conclusion: The positive secular trend towards an increase in growth and a decline in the age at onset of puberty of Thai children is correlated with improvements in overall living conditions in Thailand.
Keywords: Growth; puberty; secular trend.