Critical growth phases for adult shortness.

Previous growth studies have not explored how different growth phases-the fetal, infancy, childhood, and puberty phases-interact with each other in the development of adult shortness. In this paper, the authors attempt to describe the importance of each growth phase for adult shortness and the effect of growth in one phase on other, subsequent phases. The authors analyzed data from a longitudinal population-based growth study of 2,850 healthy, full term Swedish children born between 1973 and 1975. The height values were transformed into a centimeter score (CMS) by subtracting the raw values from the reference mean values for a particular age and sex. Subnormal growth in any growth phase, as defined by a decrease of 3 CMS or more during a growth phase, was associated with significant increased risk for final heights below 0, -6, and -12 CMS. For children with subnormal growth during one, two, and three phases, the percentages for final height below -12 CMS (a standard deviation score of approximately -2) were 0.5%, 9.4%, and 75%, respectively. Most children (57/62) with a final height below -12 CMS had subnormal growth in two or three phases. Height gains during the four growth phases were interdependent. The infancy phase was negatively associated with fetal growth (r = -0.33, p < 0.01); the childhood phase was positively associated with infancy growth (r = 0.21, p < 0.01); and the puberty phase was negatively associated with childhood growth (r = -0.10, p < 0.01).