Journal de biologie néonatale

Abstrait

Estimation of Birth Weight using a Model (Foot Length and Occipitofrontal Circumference) in a Resource Limited Setting

Nzeduba C.D, Asinobi I.N, Eneh C.I

Background: Birth weight is a very important anthropometric parameter in the newborn. It is a very important factor that determines survival in the newborn infants. However, in resource limited settings, the weighing scale may not be readily available, making it necessary that other methods of estimating birth weight should be sought.

Methods: This was a cross sectional, descriptive study conducted over a six month period (February to July, 2020) in Enugu state university teaching hospital, Enugu. Foot Length (FL) measurements were made from the heel to the tip of the big toe using a hard transparent plastic ruler. Occipito Frontal Circumference (OFC) was measured as the maximum circumference of the head to the nearest 0.1 cm with a non-elastic, flexible, measuring tape passing above the supra orbital ridges and over the maximum occipital prominence. Birth weight was measured while the babies were naked using a way master infant spring weighing scale to the nearest 50 grams. Gestational age assessment was done using the new Ballard scoring system. Data were documented on a pretested preform designed by the researcher, for this study.

Results: Out of 235 infants enrolled, 34 (14%) were preterm. Precisely 51% of the study population was males while the rest (49%) were females. The median foot length in the study population was 8.00 cm (0.50) and the range was 5.10–9.00 cm. The occipito-frontal circumference ranged from 25.50–37.20 cm and the median was 35 cm (2.00). The median birth weight was 3300 g (800.00) and the range was 1000.00 g-4000.00 g. There was a strong significant positive correlation between newborn the newborn FL/OFC model and BW with a correlation coefficients (r) of 0.883 (p<0.001). This study also revealed that individually, FL and OFC are good predictors of LBW with AUC of 0.934 and 0.967 respectively. At cut off points of 7.55 and 33.75, FL and OFC, respectively, can predict LBW.

Conclusions: The findings in this study show that FL/OFC model is a good proxy for birth weight. This also shows that FL and OFC can individually be used to predict LBW in settings where weighing scales are not readily available.

Recommendations: Foot length measurements may be included in the routine anthropometric assessment of newborn babies. Occipito frontal circumference may also be promoted as a proxy for birth weight and where possible, the FL/OFC model should be used to improve the predictive power of the two parameters.