Mid arm circumference (MAC) and body mass index (BMI)--the two important auxologic parameters in neonates.

Even though birth weight is the most sensitive predictor of health and outcome, accurate weighing and proper recording are not done in most developing countries. Most neonates lose 10% of body weight soon after birth and when such babies subsequently come for medical care, it becomes difficult to know whether the baby was low birth weight (LBW) at birth or not, to predict the outcome. Among the many surrogate auxologic parameters to identify LBW babies, mid arm circumference (MAC) was found to be the most useful and simplest. At a cut off of 9 cm, with a sensitivity of 92% and a specificity of 90.5% to identify LBW, MAC is recommended as an alternative measurement. Ponderal index is measured in neonatal period to identify growth retardation. Body mass index (BMI) is a very useful index in children and adults to identify obesity/chronic energy deficiency (CED). Tracking of BMI from neonatal period to adulthood is recommended to plan intervention and predict outcome. The mean BMI observed in the present study was 12.86 kg/m2 close to the expected of 13.