A study of growth patterns in very-low-birth-weight premature infants

Abstract

There are numerous problems with the infant growth charts currently in use. Many are based on very old data, small samples, and can only be used for short periods of time. The National Centers for Health Statistics (NCHS) growth charts, which are most commonly used to track premature infants' growth in the clinical setting, were not developed using growth patterns of premature infants. As a result, there is some question regarding the validity of these charts to track premature infant growth. In order to determine how premature infants' growth patterns compared to the National Centers for Health Statistics growth charts, growth patterns of nine female and eight male, singleton, very-low-birthweight (~ 1,500 grams at birth), premature infants were analyzed. The percentage who were at or below the fifth percentile for height, head circumference and weight from birth to three-years, for both actual and adjusted ages was determined. This study found both female and male babies had height, head circumference and weight measurements at or below the fifth percentile for both actual and adjusted ages over the three-year period. Because differences were found between the growth patterns of the infants in this study and the growth patterns in the infants used to develop the NCHS growth charts, more research needs to be conducted with larger samples of very-low-birth-weight infants to describe their growth patterns further. This study also found that although infants ages were adjusted for up to three-years, some infants' growth measurements remained at or below the fifth percentile. For this reason it may be necessary to continue to adjust very-low-birth-weight, premature infants' ages for longer than two years, which is the current clinical practice.