The primary objective of using a growth chart to track baby’s measurements is not to put her on a high percentile curve. It is to ensure that whatever percentile your baby is in, she grows along that curve.
If the curve has fallen, your child’s doctor will advise you on ways to get your baby back to her original percentile. Unless any medical illness or concern is affecting the baby’s growth, all the percentiles are considered normal.
If the baby is premature, your doctor will suggest a different growth chart to track the baby’s growth. This is adjusted as per her age (calculated from due date) but not chronological age (calculated from the date of birth).
Premature and low birth weight babies may start on a low percentile curve. But they usually catch up with their peers by the age of three (4).
Disclaimer: While the growth percentile calculator tells you what growth percentile your child falls in, it is imperative that you consult a doctor before making any changes in the child's diet, exercise regime, etc. You must remember that a percentile value is not the same as actual growth value, but a comparison of your child's growth with other children of that age group. Hence, a doctor would help you best in understanding if there are any developmental delays in your child, and ways of correcting them.