AN INSTITUTIONAL STUDY OF ANTHROPOMETRIC SURROGATES FOR BIRTH WEIGHT

Abstract

Background: Various anthropometric parameters have been studied so far to find the best possible surrogate of birth weight. Material & Methods: The present study was done among 430 babies with a normal birth weight and 430 babies with a low birth weight born at IGGMC, Nagpur during June 2007 to December 2009. Result: Mean birth weight of all newborns was 2.49 kg (±0.37) while their mean length was 45.62 cms (±3.32), mean head circumference (HC) was 33.79 cms (±1.63), mean mid arm circumference (MAC) was 9.91 cms (±0.96), mean chest circumference (CC) was 31.30 cms (±1.49), mean thigh circumference (TC) was 14.92 cms(±1.53) and mean calf circumference (CaC) was 9.98 cms (±0.88). Highest degree of correlation was found between birth weight & length (r=0.95) followed by HC (r=0.94). The cut off value for identifying LBW was 45.7 cm, 33.8 cm, 9.9 cm, 31.3 cm, 14.9 cm & 10 cm for length, HC, MAC, ChC, TC &CaC respectively. CaC with a cut off value of 10 cm was found to be the best suitable parameter for predicting LBW with 95.58% sensitivity & 92.32% specificity. HC on the other hand, though have a sensitivity of 96.74% for predicting LBW but its specificity of 83.25% was too low to make it best suitable anthropometric surrogate of low birth weight. Conclusion: Calf circumference with 10 cms of cutoff was found to be the most valid anthropometric surrogate for predicting low birth weight.