A community-based cohort study from the Netherlands involving 1690 preterm infants (25-36 weeks) and a random sample of 634 full term infants provides a more precise tool for monitoring growth over the first four years of life (J Pediatr 2012; 161: 460-5).

Key findings:

• The lower the gestational age, the lower the median value for both weight and height.  A quick glance at their tables indicate that infants born at 25 weeks gestation remained on average about 2 kg and 4 cm smaller than full term infants.  Infants born at 32 weeks gestation were on average about 1 kg and 2 cm smaller through the study period.
• The absolute differences in weight and height were nearly constant, indicating that there was a lack of ‘catch-up’ growth.  At the same time, a child ‘following his own curve’ parallel to growth curve is likely a normal pattern
• Head circumference at the end of the first year was similar between preterm and term infants
• Greater variability was noted in boys

While this study did not adjust for maternal height, it is known that short maternal height does correlate with increased likelihood of short offspring.  This is partly mediated by having a small for gestational age birth.  Other limitations of the study included that the cohort was >90% Caucasian, and there was no adjustment for multiple births.

Useful links/references:

• Growth Charts – Homepage -CDC growth charts
• Pediatrics 2011; 128: e1187-94.  Growth and predictors of growth restraint in moderately preterm-born children.
• Pediatrics 2003; 112: e30-8.  Growth of preterm infants during 1st 20 years.