A prospective study about physical growth of children from birth to 2 years old born full-term small-for-gestational-age

Aim To evaluate the growth trend of children from birth to 2 years old born full-term small-for-gestational-age (SGA) in Chengdu, China. Methods Full-term SGA infants were prospectively followed from birth to 2 years of age. The weight, length and head circumference were monitored at 3, 6, 12, 18 and 24 months. Catch-up growth and growth velocity were measured by using standardised z-score and Delta z-score. Growth deviation was analysed. Results A total of 850 full-term SGA infants were involved in our study. There were no significant differences in weight or length at birth between male and female infants. Full catch-up growth was seen in 95.85% of SGA infants within 2 years of life, with no gender differences. The z-score and Delta z-score for weight at 3 months were less than those at other ages (P < 0.05). The z-score and Delta z-score for length at 3 and 6 months were less than those at other ages (P < 0.05). Smaller z-score for head circumference was seen at 3 and 6 months (P < 0.05). The z-score for body mass index at 6 months was the largest over the period of follow-up. The total prevalence of being overweight or obese fluctuated around 10% at different follow-up stages. Males had a faster growth velocity for length at 12 months compared to females (P < 0.05). The proportion of those who were underweight, of short stature or had a head circumference z-score < -2 significantly decreased between 3 and 6 months. At 24 months, there was an increase in z-score of 0.67 standard deviation for both weight and length in most full-term SGA infants, and the proportion of underweight and short stature was 2.97 and 2.67%, respectively. Conclusions Most full-term SGA infants undergo catch-up growth during the first year of life. Regardless of gender, the catch-up velocity for weight exceeded that for length at each visit. Additional follow-up studies are needed to determine long-term growth outcomes for full-term SGAs.